Many seem to be, of course it could just be that I find their material funny because they are sceptical..
Linda Smith, Python, Billy Connolly, Dara O'Briain and Alan Davies spring immediately to mind.
And you can add Viz magazine (home of toilet humour and not as funny as it used to be) to the list:
From the latest issue, a cartoon set in a school biology lab.
Mr Snodworthy (a teacher): "Today we will be doing Biology, so you can spend the lesson dissectin gthese frogs whilst I drift off into a sexual fantasy about being spanked by the dinner ladies."
Headmaster (entering): "Ah Mr Snodworthy. I have an important announcement. This is Sir Peter Fruitcake, a wealthy local businessman who has just given me a cheque for two million quid. Consequently, this school has now become a "faith-based city academy". That means as well as taching our pupils proper science, we will also teach them any daffy load of old cobblers that Sir Peter believes in."
Sir Peter: "That's right. And I happen to believe in the existence of magical little pixies who live in the woods. So from now on instead of dissecting frogs in biology class, I want your pupils to dissect pixies."
Headmaster: "Come on then, Mr Snodworthy. Give each pupil a pixie and a scalpel and set them to work."
Mr Snodworthy: "B-but headmaster there.. erm.. there aren't any pixies. There's just frogs."
Headmaster: "Snodworthy! How dare you disrespect Sir Peter's beliefs!"
It would be even funnier if it was not so close to the truth.