I don't know any atheists who hate Christians, but many who hate Christianity. Of course not all atheists are this way; perhaps not even a majority; but it's also not that uncommon. The 'push-back' you describe can also be quite angry and bitter; it is not hard to confuse this for hatred. There are plenty of atheists who have no trouble with a Christmas tree in the public square; but the ones that do, are the ones one hears about.
I knew Madelyn Murray O'Hair's granddaughter slightly (sadly, she was murdered with her grandmother). While the granddaughter was a nice person, it was hard to conceive of someone more hateful and angry than her grandmother. She was less atheist than anti-Christian, and that position exists today in some atheists.
My husband is Christian. I'm an Atheist. The kids can go to church with him or stay home and help me out. It's a mixed bag. I don't mind my kids learning about Christianity. I don't even mind if they grow up to be Christians. I don't want them to be atheists or Christian or Buddhist by default. I want them to use their critical thinking skills to make up their own minds. My parents allowed us to go to church without next door neighbour when we were kids. They all seemed nice enough. I don't take offense until religious groups want to limit other peoples choices. Have prayer groups at school, do charitable work, put up statues. But don't stand in the way of mine or my daughter's reproductive rights. I see more than one religion trying to cross that line and I will always make some noise when that line is crossed.