What happens when you're over thirty and want to marry and have kids? Are you then not cool because you need/want to have a stable home? Are you not enough of a hacker, not 1337 enough, because you want to work for a company that might be around in 3 months?
It never ceases to amaze me how many people, who consider themselves very smart no less, by default consider anyone even five to ten years older than them complete fools for making choices that would be irrational to a 20 year old. Got news for you, you'll grow up one day, if you're lucky.