By copying and distributing the work of others you reduce the income they get in reward for their work. Take it to the extreme: if everyone in the world got hold of movies, music or software for free, why would artists and developers continue producing original works if they're receiving no reward for it? A warm fuzzy feeling that people like your creation doesn't put a roof over your head, nor does it put food on the table.

Hmm, let's find out. Maybe people will do it solely for artistic reasons, with no regards to a commercial return. If that doesn't work, then the worst case is we train all those people previously involved in the commercial side to work as something else.