Rat Races

One job listing annoyed me today - it asked for examples of website design work, but specified "no freelance". Why do they care? Doesn't the fact that I've designed and written websites on an unpaid basis mean that I'm willing to work hard, even without the carrot of a paycheck hanging in front of my face? Do they only want people motivated by money, and not a love of the field?

I could understand if I were a self-taught physicist or mathematician trying to get a job... but any artist, designer or coder worth their salt knows that in fields like this, having a formal education and career doesn't mean an awful lot.