ug...prank calls..

can anyone tell me why my friends are so obsessed with prank calls? i just dont get it...at parties they waste like an hour just calling people and saying (in a very racist Chinese voice) "hello?didyouordersomesushi?" or "Hello we work for NASA, and we are trying to break the sound barrier so please tell us if this hurts your ears(then liz will scream this horrible earsplitting high pitched scream)"...........i just dont get whats so funny about them, i mean if you just do 1 or 2 prank calls its funny but if you do like 20 it really starts to get old...