Purchasing those paintings is an investment, like anything else. If you've noticed, the value of respected paintings has been drastically increasing over the past hundred years. Private rich art collectors purchase these in the hopes that in ten years or so the bubble will have inflated even more. One day it will pop, and I think a lot of people thought and continue to think it would be during this global recession because there's been a lot of sales recently. Little did they know that the global recession didn't affect the astronomically rich in the slightest!
The real appreciators of art probably just purchase authentic paintings that were stolen ages ago. You can't publicly sell them so I doubt the purchase of one is nearly as motivated by business.
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"It's a magical world, Hobbes ol' buddy...let's go exploring!" - Calvin
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