[tombert]

In hindsight you are right, but I'll give you the mentality that 14-year-old-me had:

Basically, the idea of being racist is so absurd, that by being ironically racist I'm poking fun at the racists, not the races.

It's not a completely ridiculous notion (though it's abused heavily); satire is a common tactic for comedy. Clearly people go too far, and I don't think it's a good excuse to say "it's just satire".