I used to commute to N.Y.U. from New Jersey during the 70s. I'd get off at the Port Authority bus terminal walked through that area. There was graphic child pornography openly displayed, along with horrifying sado-masochistic images, some involving children. It haunts me to this day. That was before digital imagery. Where did those children come from, and what became of them?
So yes, "Oh Calcutta" would be Sunday school by comparison.