Actually, the western world has traditionally rewarded skilled artists and craftsmen quite well - assuming they at least entertained. Both small and large scale undertakings could see an artist at least making his way, if not being raised to importance almost as great as their leaders. There were plenty who didn't and barely skimped by. I'd wager even back then there were many more artists who were barely worth feeding than there were who created the great works we know about today. If an artist was good enough, often somebody rich, or a noble, would take him on as a patron so he could do nothing but create art, the equivalent of a professional artist today, and often recompense him quite well for his efforts.
Of course, the original musicians, sculptors, painters, bards, and what have you worked under different constraints. They couldn't record their works for one. For another, there were many more people who were working just to earn their daily bread than had extra to spend on entertainments of any sort, even in Greek and Roman times.
Even their philosophers, who were often looked upon as subversives, managed a living from their students, even putting up Academies.
Art was not looked upon as a waste of time, even going that far back. Theaters to host 14 thousand or more people were raised, at great expense, allowing most citizens to enjoy plays. Civic leaders paid sculptors and craftsmen to raise temples, statues, and other impressive works both for themselves and their populace.
Sure the Greeks and Romans both employed slaves. I don't know what % of the general population of Greeks were made up of slaves - I believe it was higher for the Romans - but citizens were expected to participate in art by at least going to the theater, if not creating some of the art themselves. In fact, the Greeks and Romans expected more of their "good" citizens then we typically do. They expected them to manage at least a household, to participate in politics, if a man to be a warrior at need, and to broaden ones mind with theater and the arts.