I hate responding to threads like these, but I grew up in a house with a mother who was an MFA professor in art history.
A couple of things about people who buy these things: they often don't hang them on their walls. They will probably lend it to a museum like the MET. Many of the paintings in famous museums have owners.
Also, art can be a very good investment vehicle, as noted.
Art is subjective, just like music. If all your looking for is technical ability, you'll never appreciate the greats. There was recently a big uproar on Art Twitter about someone who was complaining that Van Gogh's art wasn't very good because some kid painted the same cafe more realistically. In terms of music, Joe Satriani is a very technically gifted musician, but does his music hold a candle to Robert Johnson or Son House? Of course not.
Also worth noting. Often, art collectors are also some of the biggest philanthropists on earth. Investing in art and giving to worthy charities are not mutually exclusive. If you want to go down the route of being so vehemently Utilitarian, running would be judged as extremely selfish and worthless. After all, there are starving people and you are wasting calories on running?! You could be using that energy to build houses for the poor! Selfish pigs.