Go read Rachel Lucas on Ronstadt.
I have only a little to add to Rachel's comments:
In addition to their cluelessness about the First Amendment, these lefty nitwits have some real difficulty with the concept of a "free market". But the underlying problem is the sense of entitlement: the idea that Linda Ronstadt is somehow ENTITLED to my ticket fees, whether I want to go listen to her inanities or not.
(This is the same "entitlement mentality" that got Gore in trouble back in 2000: he imagined that he was somehow magically "entitled" to be the only left-of-center candidate on the ticket. Ralph Nader thought differently. But Gore, instead of debating Nader and exposing his liabilities, chose to ignore his opponent - and then ran around whining about how Ralph "stole" his votes. Memo to the Dems: You don't like other parties stealing your votes? Then STEAL THEM BACK. Idiots.)