Fightclub...
I spent the better part of my life as a dealer of comic art & illustration and I studied art of all kinds for decades, both in school and afterward. Alot fo what you posted above is really incorrect, or at least a variation of a novice look at the field of art.
First of all, high prices for art is not a recent phenomenon and "high price" is also a relative term. 50 years ago Van Gogh paintings may only have sold for $15k up to $50k or a more, but when you consider that the average CEO pay at the time was about $250-100k, then those amounts are quite high at that time. Furthermore, the vast majority of people who spend vast amounts of money on art ARE NOT thinking about investment value any more than I think my Raymond Chandler poster collection is an investment. We buy what we are interested in. That does not mean that investors are not present, but like in any field, they are a strict minority. Then, it is 100% incorrect that an artist's work goes up because he dies. It is a fallacy.
I've dealt with these uber-wealthy people all my life and while a small percentage of them do act the way you describe, the vast majority of art collectors - including the Steve Wynns - collect from a love for the material. If they can afford $20million pieces, it is no different than a person who can only afford $20 piece. You are involved at your price level and I can tell you factually that Steve Wynn patronizes the $1000 artists as well as the dead Van Goghs