In those cases, it's usually someone's friends or family that collaborate too
as they tend to know better than Edmonds/Beadle/etc. as to whether the victim will appreciate the joke or not.
(
joefish It's hard for thee to kick against the pricks,
Mon 10 Dec 2012, 15:58,
archived)
which is where most of the humour comes from.
case in point: Mark Knopfler, Howard Stern.
(
likeajackhammer,
Mon 10 Dec 2012, 16:09,
archived)