He has been a tireless campaigner against the trade rules that govern the lives of farmers in the Third World. He has also attacked the media, public schools and even poked fun at his wife's pregnancy.
Now Chris Martin, lead singer of the pop group Coldplay, has turned his anger on shareholders and profits. And his chosen target is EMI, the company that releases his records.
In a politically charged attack that has been welcomed by anti-globalisation campaigners, Martin said that he did not care that the corporation's profits might be dented by the delay in recording Coldplay's third album.
Speaking to the media in New York, Martin - who is married to the American actress Gwyneth Paltrow - said: "I don't really care about EMI. I'm not really concerned about that. I think shareholders are the greatest evil of this modern world."Martin said the album, the group's first in three years, was delayed because the group felt their first eight months of recording sessions had produced songs that lacked the "spark" of earlier hits such as "Yellow," "Clocks" and "The Scientist."
"It's very strange for us that we spent 18 months in the studio just trying to make songs that make us feel a certain way and then suddenly become part of this corporate machine."
On Monday, the band recorded for the cable channel VH1 and Martin told the audience: "Deadlines mean nothing to us. We'll sink the whole company [EMI] if we have to."
In February, the EMI share price fell after the company warned that its profits would be dented by the delay in releasing the album, now entitled X&Y and due for release on 7 June. Sales of the new album and revenue from the subsequent two-month tour of North America in the summer are expected to play a role in determining EMI's profits.
Martin's views will be seen by many as a logical extension of the work done by him and the group in support of Oxfam's Make Trade Fair campaign, which is aimed at helping farmers and crop growers in the Third World. Oxfam said it did not wish to comment on his remarks.
A spokesman for Globalise Resistance, one of the leading anti-globalisation groups, said: "His comments reflect the fact that everyone has to work for someone else; everyone is a slave to shareholders and he is being exploited just like everyone else. He will have created more money for EMI than they will ever have created for him in return." He said Coldplay fans should respond by downloading the band's music for free from unauthorised file-sharing websites.
While many recording artists will sympathise with Martin, few have been tempted to bite the hand that feeds them in such a public fashion. Steve Randall, guitarist with dance collective Faithless, told The Independent: "While I don't expect anyone to feel sympathy for pop stars tied to lucrative record deals, he has raised a very significant broader truth, which is that capitalism and the profit motive are not the best ways to organise the world."
EMI, the world's third-largest record company has issued a statement suggesting it is relaxed about his opinions: "We don't expect or want our rock stars to be stockbrokers."
The group was formed in 1998 and has become hugely popular in the US. Their first album, Parachutes, sold nearly 6 million albums, while their second, A Rush of Blood to the Head, sold more than 11 million.
* ...celebrity: "Fame isn't all it is cracked up to be. Everything is subservient to celebrity. Great things get ignored because they're not famous but people can tell you who's dating who."
* ...Third World poverty: "I'm a father who travels a lot and has seen how rich nations exploit poorer ones through crazy trade law and huge debt."
* ...Gwyneth Paltrow: "This is all very weird because she's a big Hollywood star and I'm just the bloke from Coldplay."