From Isaac's anti-Rockstar-attitude discussion (a very cheap summation of it), comes the question:
[The rockstar conversation] brings up some other issues that may be worth talking about here: the meaning and value of the image in art and in life (particularly the image of the artist); whether or not an ethical artist (i.e., a nice guy)creates better work than an unethical one (i.e., a preening asshole)--or put another way, whether, for the good of one's work, it is better to be nice than an asshole.
If I wasn't in the middle of the show, I'd write at length, but instead I'll just put out one point.
If we lived in a much more supportive environment -- read: indulgent -- for artists, then maybe the unethical artist could win. After all, rock-stars get ridiculously wealthy and can support themselves, therefore they can be big enfants terribles and there's no problem.
In the interdependent world of theater, however, for most artists their reputation is their business. I cast shows based on working relationships, based on how people relate to each other, more than I cast shows based on an audition, or based on some incredible success in their past.
If someone arrives with some incredible bullshit behind them, or with a reputation as being selfish, egotistical, or a poor team player, I will overlook them. Hell, if someone has a reputation for being consistently late, I will usually move on to more reliable folks.
Therefore, on the practical level, the answer is that the ethical artist will create much better work than the unethical artist. They'll work with better people, more people, and get more support -- support being the watch-word we live by. They'll build an audience better, build an ensemble better, and in the end it will make their work better.