I have several small exotic pet stores in my area as well as the better known "big box" stores. I have brought home snake mites from the big box stores so I avoid them now. Of the smaller stores, two are well-known for selling sick and/or mite-infested animals so I have never been to them. The last store gets all of my business.
That said, after attending an expo I do immediately shower and wash my clothes when I get home, because I don't know every vendor there, and some just aren't that great. It doesn't matter whether or not I touched any animals there. I only go to one or two expos per year though, so taking extra precautions when I do isn't a big deal.
It depends on the collection and how much you value it. Some people don't permit anyone near their collections, period, not only to limit the spread of diseases but also because people like to run their mouths, and just like any other valuable, you don't want it getting around that you've got a fortune in snakes... or guns... or artwork... or classic cars... at your home waiting to be stolen. It's a security issue.this one post made me laugh when reading it because i thought to myself holy cow is she serious. How in the world can i do that i enjoy my animals so much and i want my friends to enjoy them as well do i need them to fill out a questionare before they can come in. I started thinking that snakes, dogs, cats, etc all descended from wild animals but because dogs and cats where demistacted they where welcome in our homes around our friends and families with out fear of taking our clothes off when the walked in the house and immediately showering. I guess my point is that these animals have become resilient to a lot of bacterias because we didn't put them into a room and lock them away. One of the articles i read said that instead of trying to find ways to keep out reptiles isolated lets try and make them able to cope with a wide verity of situations. Now too hot or too cold yea that effects everything so yes i understand that point. I would like to hear others points of view
OTOH I've got friends and customers for my firearm business who don't own exotic pets, who never considered owning exotic pets (mainly because their wives are against it LOL), who I don't mind checking out my snakes if they show any interest.