I would imagine that the really big names would prefer to go to something like this if there's less visibility, and therefore less pressure on them to 'perform'
Just a guess, but I feel like I would want to go to events where I could actually participate
p sure the concern is publicity. doesn't matter how small an event is, the question is do u wanna put up with any scandal/slightly weird thing from the event being associated with you. if any big celebrity went they'd keep it super secret and like... wear a semi disguise or smthn