This is a good example for both sides of the debate.
I can appreciate why an artist would express the wish to keep their art out of the clutches of business. However, at the end of the day this is about one party attempting to force their will on another party and whether the motive is good or bad the end result is bad and it is the result that we wish our laws to address.
In a kinder gentler world without copyright something like this would become a non-issue because everybody would be used to being able to express themselves as they wish and reciprocity would demand they allow others to do the same. In our current lop-sided system people can gain control of an expression either by being the first to get there or by wresting control from another. Our mistake was giving them a sense of entitlement to control in the first place.
In matters like this, control of another cannot be a legitimate right and therefore regardless of how you feel about the other person's behavior you have no right to interfere.