I didnt personnaly mind the balloons, they looked wuite good all in the air, and were a distraction from the wait to go in, I only started minding on a few things which are -
People started to pop them deliberately with keys or other objects they had with them, I did see this being done, and being big balloons they made a big bang and made me a little jumpy. Its fine to have fun and bat them around and throw them in the air, but theres no reason to deliberately pop them so they bang that just ruins the fun for other people. Also in agreeance with Nightfox if the person who threw them over the balcony didnt want them to be popped they shouldnt have thrown them over because as well as deiberate popping, accidents do happen.
The second annoyance was that in the dance in the bar the lighting wasnt great (not a complaint it was just darker than the lobby) and being in fursuit which adds to vision impairment, someone kept throwing these large balloons at me and other suiters. There wasnt alot of room on the dancefloor and it was difficult to dance whilst not stepping on balloons and falling over. Also being hit on the head with several large ballons from differnt directions was a little disorientating and put me off my dancing. I didnt mind it at first when I first came on the dance floor, and bounced some on my nose, but after a while of having these things thrown at you from all directions the novelty soon wore off and I left as I almost slipped on one on the floor.
So whereas its fine to have fun, I think just common sense should apply.