I don't think it's any more complicated than pizza has positive emotional association and this it hooks people into talking about it.

I'm reminded of a discussion I had about how epstein gets talked about a lot because people like having an excuse to recount their teenage years. Epstein was enough to go "oh no that's terible!" but still enjoy the recollection.

In contrast no one wants to starts their day talking about genuine pedophilia, the story about 5 guys who molested an infant isn't something normal people like talking about for weeks on end. Gross.