Do you realise that Stalin and Mao are responsible for more deaths than Polpot? Maybe we shouldn't care about the two million people that died under Polpot's leadership of the Khmer Rouge.
Just because other people were doing it, and still are, doesn't mean his crime is any less stupid and morally reprehensible. The reason he has gotten so much attention is due to the image he created/the PR firm employed by his agent created of him.