I've not met many "famous" people (well I say famous because I was only a little kid at the time. lol) but the rudest I have ever encountered was Mathew Marsden (one hit wonder & played Chris in Corrie, Sally had an affair with him??) Think the year was about 1997??
I was at this concert outside Manchester Apollo (Mizz Magazine road show I think) there was a concert on that night & he happened to be one of the supporting acts...baring in mind my mum loved this guy!! & anyway I got to meet him.
I asked him if he could sign his autograph with my mum's name... he said "no I don't do personal autographs" C'mon now this was for my mum!!.. He was so rude & arrogant.. my mum was heart broken when I told her what an absolute ass he'd been to her daughter when I was just trying to do something nice for my mum.