Well, Mr. ilovefirearms, since you asked so nicely:
Exalted violence:
The crucifixion, basically the torture and violent murder of Jesus, is seen as the pivotal moment in Christianity. It is, essentially, the birth of the religon. This event is poetized, discussed, read aloud, and even rein-fucking-acted by Christians all over the world, and the symbol of Christ dead on his cross is the single unifying symbol of the religon. Also, Catholic saint-hood is filled with martyrs abound, and the act of dying painfully for your imaginary friend is seen as the absolute best way to go to meet him. ALSO, the Crusades. ALSO, the Inqusition. ALSO, the witchhunts and burning of pagans and nonbelievers for centuries.
I think we got exalted violence covered pretty well, ne?
Antisocial behavior. This is actually the hardest of the three to show examples of. Isn't the church itself a social circle unto itself? Well, it is, but it's still not society at large, which the church regularly shuns in favor of it's teachings. While all the other kids are having sex, doing drugs, and living life, you sit home alone and read from the bible.

Not to mention the Catholic church's interest in politics, which are sure to get your ass reverse-shunned by the community. I dare you to tell people in the general public you don't believe in handing out condoms in Africa. See how the average "man on the street" would react to that.
Having all your friends be the same religon as you, going to a school based entirely around your religon, joining groups for no other reason than your religon, voting certain ways for no other reason than your religon.... A very socially minded lifestyle.
Finally, and by FAR the easiest, is the trivialization of human sexuality.
Really. Do I have to say anything about Catholism and sex? I mean, I CAN explain this if you'd like, but really, it's pretty goddamn (tee hee) obvious.