I can see someone doing this because they think it's funny. I could easily attribute this to 'rich person' behavior, and people in Hollywood are weird. What concerns me more than the existence of the party is that there were enough people willing to attend it. Like an edgelord hosting a 9/11 themed party. Costumes could involve hijackers, dead passengers, dancing israelis, etc. The host and hostess might dress as a pair of towers and they're really hoping someone will come dressed as a jet and ram into them. Is that 'edgy'? In a juvenile way, sure. Is there a joke in there? Not a very good one, especially considering the amount of work. Could you find enough people to populate this party? Probably not. In the end, harmless but dumb. Except that if anyone went to this party, I know they are not actually plane hijackers, just people dedicated to a dumb joke. A pedophile party is a coin flip I would absolutely not want to take.