What is it with atheists and ramping up insults on holidays?

Two reasons:

1) atheists are neurotically obsessed with what other people believe about God.

2) hatred versus religion is often supported by the media and forum moderators who prefer anti-religious hatred over that of anyone having a religious opinion.

Two things, OP: First, someone who does not happen to share a belief in the same mythical deity as others cannot automatically be deemed an "atheist", as you (rather carelessly) are insinuating, here. There are many deeply spiritual (& intellectually advanced) people on this forum (and throughout the world) who take offense to "Christian holidays" for very good reasons...one of these reasons being that, as in the case of "Easter", early Christians blatantly stole these holidays from the ancient Pagans, and, worse, all but eradicated the remaining Pagans (of the time) & many remnants that would serve as proof of the true origins of the celebrations. Worse yet, modern Christians - such as those that have been posting on this forum - completely ignore the fact that their (utterly plagiarized) belief system was founded on the bloodshed of the innocents that were slaughtered by the early Christians when "Christianity" was invented by the mortal men who were in power. Do you not realize the great disrespect that YOU show to the millions that have been murdered by Christians, throughout history, by claiming that all should somehow show respect to those who are now, in effect, celebrating these murders, in these "stolen" holidays? Simply put, your statements make you seem wholly uninformed & lacking in any hint of understanding, yourself. And, secondly, there are profoundly intolerant, hateful & entirely vile posts on this forum - and elsewhere, in the world - by Christians nearly EVERY SINGLE DAY (such as the homophobic, racist & otherwise bigoted rants that appear so frequently :-( ); why does such horrible, inhuman behavior warrant any respect or consideration, in response? Do you personally believe that Christians are better than everyone else on this planet, or that Christians should be allowed to say & do whatever they like, without repercussion?