FYI, correct lingo is "slammed". It's partly to keep it out of the way, partly to save weight (only need a tiny seat post), and partly just cause that's how everyone else has theirs.

The no brakes thing seems to be mostly fashion, but most of the fashionistas will swear up and down it's a weight saving thing (how much does a brake weigh, seriously) or that it makes them flow better.

Some people do ride well without brakes, others mostly just scuff the **** out of their $200 shoes...