Schadenfreude: pleasure derived from the misfortune of others. Or if we break the word down, Damage-Joy; ‘Schaden' meaning damage and ‘Freude’ meaning joy.
The reason Laurell & Hardy, Itchy & Scratchy and (insert country here)’s Funniest Home Videos are so popular is that it’s enjoyable to watch someone other than you take a pie to the face or getting hit in the groin with a football. There is research to show that this is the most universal, and therefore it's theorized, oldest type of humour. If this is the case, if laughing at others really is that basic why do we still use an obviously Kraut word to describe this phenomenon? Why hasn’t a shorter and easier to spell version of the word entered common usage? The closest English word we have is slapstick but that is the type of comedy rather than the actual act of “Ha! Rupert just slipped on a banana skin.”
There is a touch of shame associated with laughing at other people’s misfortune so perhaps by keeping the Germanic moniker it somehow allows us to blame them for this theater of the macabre in much the same way as we blame the French for rudeness, Americans for obesity and the Canadians for Tom Green.