[onion2k]

If their skills aren't marketable in free market, why should other people subsidise them?

Lots of things that society has collectively decided are they would like to have aren't possible in a free market. Roads are a good example. If people had to buy their own roads you might have freeways but towns would be dirt tracks. Roads would be wildly different around the country. Signs wouldn't be unified by design. It'd be awful. The military is another example. If people actually had to buy military things in a free market you'd have a fragmented market of tiny militias and absolutely no national defence infrastructure. The list of things that are only possible to pay for in a socialized way is very long.

There's no reason why increasing the supply of art beyond the limited amount that the free market will provide isn't another thing that would make society better.