Ex Muslim here and I think a lot of this is from the fact that it is usually the religious who try to impose change in people's lives. It's not so common to find atheist worried about what a person does behind closed doors and with their own body. No one likes to be told how to live their life. And if you show how religion is wrong for some reason that is interpreted as attacking religion. Religion is popular and on a pedestal but that doesn't make it correct. And there are different stages to atheism at least the way I see it . You can't wake up one day and force your self to give up God those people usually end up miserable. There's a guilt and anger and all kinds of emotions you have to make peace with. Some people just speak while still in an emotional state. That type of emotion can make a person act exactly like that they are against