Why do a lot of atheists claim that there is no evidence that God exists?

Closed minds.

Even believers wouldn't ask for evidence that God exists – because that would deny the need for faith.

I was religious from childhood, and have always been interested in religions, mythology and science; I was a devout, practising Catholic; I read the Bible, both Old and New Testaments and the Apocrypha, several times; and was taught about it in school.

After studying and thinking deeply about faith, I realised in mid-teenage that faith was based upon nothing but itself, that science explained nature satisfactorily without needing supernatural beings, and that religious beliefs were no different to those of ancient beliefs in gods and goddesses.

When I first had doubts about my faith I thought that maybe this was a test of it, which was an idea planted in my mind by those teaching us about our faith. So I made the effort to accept it even more so. But the doubts came again, and I wondered what would happen if we took faith out of the equation; the world and nature still made sense, so I saw no reason to get back into it. And my understanding is that there's no theoretical or mathematical need for a god or gods, and there's no valid evidence of it or them; so there's no reason to believe. At the time this was difficult intellectually and emotionally (I was a teenager, after all).

That was over 40 years ago, and my escape from faith has freed me to embrace what science has to offer, which I consider far more plausible than belief in the supernatural, and is the nearest we can get to the truth about how nature and the universe work. I've felt a sense of freedom ever since, and am happy and at peace with this. And I've found the humility to admit that I don't know everything, rather than masking this by invoking a deity.

I still have an interest in religions, mythology, folklore and related matters, and am fascinated that people still believe in things that to me are clearly just not true.

Not a lot, all atheists claim that. If there were real evidence of the existence of a divinity there would not be any atheist. Believe because I say so (the real definition of faith) does not a proof make.

So you have evidence ? I ask b/c we ask all the time and we get answers like "Birds are pretty" and "Humans can't build butterflies" and "Love exists" and other such drivel. Do you have a photo ? Do you have God performing miracles that were documented by a team of scientists ? Do you have anything that doesn't seem like a con ? And this 'God', does he love us ? And is he 'omnipotent' ? B/c if so, then please, by all means, give me perfect health, add an inch or two to my penis, make me 18 years old and give a good job or a briefcase full of 100 dollar bills. I mean, he is OMNIPOTENT right ? And he LOVES ME, right ?

I see that you have presented all the evidence there is that God exists in your additional details. That's why.

If you understand the myth or mystery you'd realize it's all about getting in touch with your own subconscious mind, not worshipping anything. The Judeo Christian myths are gnostic tales of gnosis or enlightenment. The Gnostics considered the old testament god that christians, jews, and muslims all worship to be the inferior god the material dimension, the Demiurge, but had a higher supposably unknowable god which is You.

Probably because there's no evidence that God exists.

there is no evidence for the existence of god. humans have imagined a higher supernatural power since the stone age. here is a short list of those gods;

http://www.youtube.com/watch?v=zZVRpqm0Cl0

Because arguments in favor of the existence of deities are constructed of logical fallacy.

Well..... show them some evidence and they'll stop claiming that he doesn't exist....that is, if you can find any evidence

Same reason people say there is no evidence magic is real, despite Harry Potter books saying it's real RIGHT THERE. Plus, they include London which is a REAL CITY.