Sea Breeze
I do not think any people are "all alike" but I have some thoughts re your question. I have an old schoolmate I've vaguely kept in touch with on social media, because at a difficult time in my life he unexpectedly reached out to me so I've always wished him well. He is, or portrays himself as a rather militant atheist, posting a lot on religious hypocrisy, contradictions in the Bible, believes in science above all and appears to think all religious belief should be wiped out. I also sense in him though feelings of loss and anger at himself, so try to send occasional positive non-religious thoughts. He frequently complains of being lonely, not being able to find a woman friend or companion. I think his approach to others may be so intense it frightens them off...so I think perhaps some atheists, feeling unable to rest their hope on anything because they fear it will lead to disappointment and sadness, somehow resent seeing feelings of hope and assurance, religiously based, in others and so, want to fight or push against it...
Coincidentally I had to "be" an atheist in a ministry demonstration at the Hall last night. Did not believe in God because of religious scandal, suffering in the world, and that when he 'died' and was resucitated during an operation there had been no 'afterlife -near death experience. Brother set up return visit by saying Jesus condemned religious hypocrisy, the Bible speaks of the dead being non concious and there is a wicked ruler of the workd at present...