:lolol: He doesn't have to really.
Admittedly some are funnier than others
To Simon Kelner, republican editor of The Independent, at Windsor Castle reception:
“What are you doing here?” “I was invited, sir.” Philip: “Well, you didn’t have to come.”
That’s quite funny :shrug:
Which is quite funny. He has got to break the ice somehow and he does it in a playful way. They are the sort of jokes Jimmy Carr and Ricky Gervais would be proud of. He probably does it to wind Liz up as well.