There is always a queue. From the moment it opens to the moment someone finally drags people away from it, there is always a queue.
Booths give your guests something to do with the parts of the night they aren’t dancing. Props, silly hats, four people crammed into a frame designed for two, and prints they take home the same evening. The video version catches slow motion clips and boomerangs of the same nonsense, which is the stuff that actually gets shared.
You get a guest book full of photographs and scrawled messages, plus a full gallery afterwards of your friends behaving in ways the official photographer never saw.