Because those are the atheists think they are special and that they are the only ones who should be exempt from persecution. The honest truth is no matter what religion you practice some one will persecute you for it. Should people do it , no. Christians are taught to be accepting of others, somewhere along the lines they forgot it, Muslims are taught very similar. Buddhists I've found to be the least holier than thou. It comes from being insecure in ones faith(or lack there of) the more insecure, the more they dog on other people to try and convince themselves that they are better.