I'm not sure what quilt shows in USA are like, but the small local quilt shows around Sydney Australia usually feature a stall selling items donated by the local quilt group -- sometimes small gift items, unfinished quilt tops, but best of all are the fabric bundles of unwanted material! I race past the quilts on display -- they will still be there in half an hour, but the fabric bundles sell out fast.(And there will be no more to replace them!) I have purchased yardage to use for quilt backs as well as lots of fabric pieces for only a dollar or two. There are usually great bundles of back issues of quilt magazines -- 3 or 4 for a dollar, which give me hours of pleasure and then get passed on to others at my group who can't afford magazine subsciptions.(At that price it doesn't matter if they duplicate issues I have already seen).
Then there are all the wonderful quilts to examine, sometimes to discuss with other viewers, sometimes to silently comment "I wouldn't have used that border". I have found that the more shows I attend, and the more quilts I study (as opposed to just photos), the easier I can decide my own taste in styles, colours and designs. Finally, there is always morning tea/lunch with lovely home made sandwiches, cakes and slices (I even take a small plastic container so I can buy a few home made items to take home).
Can you tell I am anticipating eagerly the next quilt show?
(Regarding photography: there may be local rules, but it seems that as phones with cameras have proliferated, most shows here have given up the battle to stop photos -- I leave it to others to comment on the rights/wrongs of that issue)