everyone brings a few juices (if they can) to trade or pass around to try, trades for HW (e.g. I keep getting these putrid pink drip tips when ordering red ones - I would trade them for almost anything), check out other people's gear (I usually bring 4 or 5 mods to let people check them out). I gave away a stealth box mod at the last one I went to...
Mostly just a bunch of vapers getting to talk to other vapers and have some fun.