Elton John is actually crying censorship because there are not enough anti-war songs being written out there, and that people get booed if they are anti-war. That's not censorship, that's people disagreeing. Maybe more people would write anti-war songs if more people were against the war. Was it censorship when Linda Rondstadt interupted a concert that people had paid good money to see to tell everyone to go see Michael Moore's movie? No. Was it censorship when she got booed off the stage, when many of the concertgoers stormed out of the theatre and tore down her posters? No. That was people who paid good money to see a show getting upset that she couldn't keep her mouth shut. It would have been censorship if she had been hauled off to jail, but she's free to go play somewhere else, and get booed off the stage anywhere she wants, except the place she played, which said they won't allow her back.

The same logic that allows Elton John to cry censorship in such situations would lead to Pepsi-Cola saying they are being censored because Coca-Cola has a higher market share. They aren't being censored, the consumer is making a choice.