I sometimes spoke with the artists in the "stable"; many were self taught but quite good. The advantage of the print market was that the original paintings often sold for much higher prices. Somehow people get the idea that something that has been commercially reproduced has some kind of mark of quality or selection higher than that of run-of-the-mill gallery works ...
The danger is that sales will drive production, you've mentioned as much. Personally, I don't think the masters minded that much, and in fact I've never seen that as a drawback. If we take history as any kind of lesson, many of the great works were as much driven by a desire to make some serious jack as they were to serve some lofty liberal arts ideal of Art. I don't think an artist has to starve unless they want to be some kind of victim.
Jeffery