And if you bake bread just for the money then those breads probably suck anyways. And if you write software just to make a living then that software probably is trash. And if you build cars, or waiter at diners, or drive taxis, then you probably just deliver bad, bad goods and service.
Bread isn't art. Neither is any of that other crap you've mention. Your analogies fail. Many classical and romantic artists didn't live under nobility. Mozart was an independent musician yet he's arguably still one of the greatest composers of all time, without the need for copyrights. Of course, you tellingly ignored the examples of Plato, Aristotle and others so you can cherry-pick your argument.