Because, anything that's described as "EMO" "Goth" or "Metal" is seen as appealing by the tools that surf ebay. Thus, it sells! Some items are even listed as coming from Hot Topic. If that isn't cool, I don't know what is. *sarc*
My grandfather told me that back in the early 40's, when we Soviets were fighting the Nazi scourge, German issued jackboots were nicknamed "Emo" by us Russians. Soon this evolved into us calling the entire of Nazi Germany "Emo".