Because not everyone's team sucks.
It's not the teams. It's the game. NBA ball differs vastly from the college game. Slam dunks should be a 1 point score. Either that or the rim should be at 12 feet. The personality disorders that go on display by overgrown adolescents before, during and after the games are cringe worthy at the very least. I could go on but if you love the NBA experience, you'll still be unconvinced.
What is the purpose of the season when more than half the teams (16/30) get into the playoffs?
And don't get me going about the lottery picks in the draft...