You also need to realize that most show promoters do not vet their vendors to ensure they are only selling healthy animals; anyone who wants a table gets one. So, you could have one vendor who breeds and sells his own critters set up next to a vendor whose wild-caught, stressed, parasite-riddled critters came off of a plane from overseas the week prior to the show.
Since you have decided which shows you are attending I would strongly suggest going to the show's Facebook page or web site and doing some research on the vendors well before the day of the show. That way you will know who to avoid.
I wrote this up a while ago about buying from online vendors, but the how-to-research aspect applies just as much to vendors at expos.
https://ball-pythons.net/forums/show...g-Herps-Online