Well, if we want to cover the hippy tree huggers, there is a Penn and Teller video on youtube right now where they sent someone to a tree hugger convention of some sort with a petition to ban dihydrogen-monoxide.
https://www.youtube.com/watch?v=yi3erdgVVTw
They got hundreds of people to sign up based on spurious ideas such as it being found in lakes and rivers, being used by the nuclear industry and Styrofoam companies, it is used in pesticides (thus when you wash your produce, it never really comes out), it causes excessive sweating and urination, and so on.
Of course there is nobody really famous in that clip but hundreds of lefties signing a petition without taking a moment of thought or stopping to ask a single question is not exactly the best move. Basically, they have decided to let other people do their thinking for them so long as they get to feel like they have done something good at the end of the day.
Then too, if you want a famous left leaning hypocrite, just remember that video clip of Bill Clinton saying that he did not have “sexual relations” with Monica Lewinsky. Well, sure, every guy on the planet has been in a locker room when someone advanced the idea that what those two did “does not count as sex”. Yet we all know the truth on that score.
https://www.youtube.com/watch?v=nP5FunbZvJ8