catered is another word for supply of drugs to celebrities, see drug dealer. If someone says the party was catered it normally means drugs are available and free.
If your asked to speak with the party caterer for a celebrity, you may well be asked to order drugs, not
sausage rolls or bits of
cheese on a stick!
Unless they want you to talk with the party caterer, you may want to clear that up! less embarressing than asking for a couple of bricks, and the dude in the tall
white hat has no idea what you want!