Hm I'm personally not a friend of religions in general. Now while it is definitely true that religions can help a lot of people through hard times and what not, I have the feeling that more often than not - especially in the case of all too faithful subjects - they can do more harm than good.
Of course it always depends on the type of religion; but in any case, any religion that is practiced to an extreme is bad. As soon as faith turns into fanatism, you got a serious problem at hand. I believe that religion should not be regarded as an excuse to act like a complete loon or moron in your life and towards others, simply because you believe that "you will get 70 virgins in heaven if you blow yourself and a couple of infidels up" or you can think you can do whatever you want because "God will forgive me in the end anyway". Don't get me wrong - essentially, most religions convey quite useful ideas and good principles. If you read the Bible, you got a lot of good messages. Especially if you read the Koran, you get a lot of great messages - I mean, I've read a few passages, and the essential messages and principles told are really great. The problem is that a lot of people over-interpret and over-stress certain issues in order to promote certain views or achieve certain ends, and thus quite often distort and work against the very ideas that are good behind those principles.
If I look at Christianity, I see no point in believing that the "afterlife" will be so great, so it really doesn't matter how crappy my life right now is, since once I'm dead, I'll be well off anyway, since God forgives all sins and what not. I'd much rather focus on my life as it is, and try to make it better because I want it to be better NOW - well, if there IS an afterlife, and if that's good as well - well, count me in! But I'd much rather try to be a decent person in this life, and some create a decent life for myself right now through work and actions and my general attitude, than to rely on some religion to bring me "joy" once I'm dead.
And as for being a good person in life today - seriously, I don't need any prophet or messiah or God who tells me how to be a good person. I believe we all should at some point reflect about "good" and "bad" as far as our actions are concerned, no matter if our parents teach us or if we just start thinking about these categories, about what is "right" and what is "wrong" ourselves at some point in our lives. When living in a society, sooner or later you will have to think about these elements. I believe that in earlier centuries, religion was often employed to confer the principles a society wanted its members to live by to these members; of course it is easy to tell someone to act in a certain way if you tell them that this is the "will of God", of someone or something more powerful than yourself, of someone or something who created you, and who will judge you by your actions in the end. But as said, it is a simple way to "teach" people, and often enough the basically good ideas behind it are corrupted, sometimes bent and sometimes broken - and once religion is institutionalized, bad comes to worse.
For if anything, belief should be something very personal. I see no point in following the ten commandments or whatever other rules any other religion might impose on me, simply because "they are the rules". I want to follow my own principles, and I want them to be good. And not because I want to "go to heaven" or whatever, but because "good" is beneficiary in and of itself; be it towards me and/or towards others. It should be the desire of each and everyone by themselves to lead their lives in a way that is essentially "good", and it should be everyone's duty to think about what they wish to believe in as well - and they should believe in something and act accordingly of their own free will, and not because some age-old traditions and conventions (apparently) force them to. As free-minded human beings we should be able to reflect about our actions and our attitude and about the way we behave in our lives and vis-á-vis others; and we should be able to discover what is "right" and what is "wrong" because there are some basic moral and ethic values that should be inherent to our comprehension. I don't need to read in a book that I should "Do unto others as you would have others do unto you" - I should be able to realize things like this myself by thinking about them; should be able to realize that I should not act in a way that, if someone else acted like that towards me, I would be mightily pissed.
But I guess in this department, religion once again serves as an "easy way out". You take some pre-formed principles that have (apparently) stood the test of time (though not always for virtuous reasons, as history has shown us) that others have conceived, and live by them because "someone" tells you to. I really think it should be in everyone's own interest to ponder the ideas of religions, but also the very elementary moral and ethic principles they are based on - because it is those principles that should be the integral part of what religions can teach us on how to lead our lives; and not pointless conventions like "going to church every Sunday" or "saying ten rosaries before going to sleep". I think things like those have or should have nothing to do with belief at all; but people all too often attach themselves very closely to them, expecting redemption or salvation from pointless acts. I think that it would be much more useful, and much more purposeful, and also much more in the sense of EVERY religion - no matter if we're talking Christianity, Hinduism, Islam, Buddhism or whatever, because the underlying ideas are always quite similar - to ACT and do something good in your everyday life, something that is beneficial to yourself (and not at the expense of others!) or beneficial to others, instead of expecting a glorious afterlife because of knowing the words to five prayers by heart.
Alright, I'm just realizing I've once again ushered into a rant, but I'll try to finish this up now lol... Anyway, as said, I think these rituals and religions generally were used in past times to more easily regulate peoples' lives - but I think this is - at least in many parts of the world - not necessary anymore, and people should really try and work on their perception of "good" and "evil" themselves, and try to improve their way of living accordingly. Religions can definitely be a good starting point, I will not take that away - but I think that it is the underlying principles that should matter, and not whether you have a "messiah" named "Jesus" or a "prophet" named "Muhammed" or a million of different Gods or whether you call a god "God" or "Allah" or "Jahwe" or whatever. I think that the core of religion, and the good they can do lies in their ideas, and not in their names, or the names of their prophets, and not in their rituals, and not in their conventions, and not in their promises of a glorious afterlife or an entering of the Nirvana, and not in the words of their prayers; but in the acts they can inspire that can have a beneficiary effect on our lives today - for this is truly the only thing we can have influence upon. For even if I "believe" in an afterlife, and if I "believe" I will be forgiven all my sins, even if I "believe" I will enter a state of cosmic equilibrium - it remains a "belief", and not a proven fact - but the facts of reality that surround us, those are real (or well, at least as real as anything can be proven real, but that is subject for another debate lol); and upon those, I can have an influence on, and these facts I should try to improve. That way, I can try to lead a better life here - and if it works, and there "really" is this afterlife religions promise you; well, then all the better. But if not - then I have at least used the time I was given in a useful manner, and had some "good" here while it lasted, even if the promise of eternal life and bliss ended up being not true.
Now as you can tell, I'd probably consider myself an agnostic. I do not believe in any "God"-entity. But I also cannot rule out the possibility of there being one. You can't prove one way, and you can't prove the other way. So I also do not understand those advertisments the thread starter mentioned - and I also see no sense in propagating atheism. In the same breath you ask "Why should you believe in a God?", you could also ask, "Why should you NOT believe in a God?"
So I guess, if someone wishes to believe in any religion, why not? But this religion, and (blindly) abiding by its rules, should not be used as an excuse or considered an absolution from thinking on your own, and reflecting about your own principles. Whatever cards fate has dealt you - they are yours to play, and yours alone. And if there is a God who will judge, or if there is Karma that will judge you - this we do not know. But I know that for myself, that at the end of the day, I at least will have to be accountable to myself, and will have to answer to my conscience on the day of MY judgement, and I wish to pass that test once the day comes.
So my "belief" basically is that people should find something that can help them lead a "better" life. If that is some religion, so be it. If it is some philosophy, so be it. If it is their own ideas they discover through thinking and reflecting about them, so be it. I think these ads should not be advertisments to "not believe in God" but be advertisments to "believe in yourself" and think for yourself, instead of subjugating yourself blindly to rules and conventions for the wrong reasons.
What I want to say is this: If at some point in your life, you have to ask yourself
"What would Jesus do?"
you truly should be able to ask yourself
"What would I do?"
