Talthyr - That's good, be a lawyer. Society needs people like you to make fun of and kick around.
Just remember, YOU'LL be the one laughing all the way to the bank.
I think that it is difficult for teachers NOT to categorize their students and treat them all the same, especially at first. A typical HS teacher is responsible for 150+ (a teacher I observed last year had 192!) students for an hour a day. It's hard enough just learning all the names, much less how to treat everyone as an individual.
Eventually, the better teachers get to know their students individually, and show them respect and treat them as adults, which pays off in spades as far as creating an effective learning environment goes.