And if you don't know a free-loving coworker or something, it's easy to have all sorts of abstract hatreds towards these "menaces to society." I met an East German guy who started working in Cologne a few months ago, and he shed his homophobia pretty quickly because he had 4 openly gay coworkers. He'd inherited his homophobia from his father, and hadn't had cause to question it beforehand.
Incidentally, this CrimethInc piece on adultery pointed out all the paranoia and rebelliousness which makes an adulterous lover feel like "a traitor to the entire civilization that raised him": http://www.crimethinc.com/texts/atoz/adultery.php
It's easy to judge others; I'm sure we all do it. One tiny step to essentially conducting surveillance on others.
We've all been wrong in some of our judgements. Is it so hard to see why homophobia happens?
Tayssir