And YY to what Jassy said - far from finding charity in the name of religious all wonderful and some sort of proof that religion is great, I not only think that charity with strings attached is not true charity, but actually a form of manipulation and bribery, I believe that if people only donate to charity or do charitable works because they believe they have to as part of their religion, then I find that actively immoral, even if the result is positive.
Why the lie exists that Atheists can't be moral without religion, I do not know. If people need to be coerced into being decent and caring via religious manipulation (ie fearing God's wrath), or they need to have it explained and reinforced constantly, then those people are deeply inadequate, probably amoral, possibly even sociopathic.
Of course, the truth is that nobody normal and decent needs any spiritual push, motivation, or threat in order to be a good person. When a religious person claims that they need (or others need) religion in order to be moral or charitable, or whatever, they are actually making themselves look incredibly weird, pathetic and dodgy. It is an INSULT to suggest that any adult without serious problems of some sort needs help to know right from wrong.
This is another reason why religion is annoying to many atheists; it infantilises adults, it actually demeans and diminishes not only the truth about individual and collective possibility for good, but inhibits the possibility itself, it stymies the potential, breadth and reach of that possibility with its disgusting and inhumane proclamations on who deserves it and who doesn't, etc., and it actively works to prevent people using their minds and intellects fully, to develop and strengthen rational and logical capacity, perception, analysis, and serious thinking of any sort, and it diminishes people's lives by giving them an incredibly narrow focus and framework with which to operate in. I know loads of religious folk will want to wax lyrical about how it opens their world up and so on, but trust me, when you're observing it, that is so far from the reality that it's heartbreaking. I'm not just an Atheist because there's obviously no god, I'm personally an Atheist because I'm a humanitarian and to see how religion limits and infantilises people and their intellects, morals, lifestyles and personalities, is genuinely heartbreaking.