I will agree and disagree with you here. Its the same for online. If you buy from a random person on kingsnake u may never be in contact with them once u get the snake.
But if you buy from good vendors at your expo a lot of them have been in business quite awhile and most of them all have business cards.
So it is a downfall the thing is to just make sure you grab that business card before you leave the stand
Me i dont like buying online unless its something REALLY good. Because i can find exceptional examples of the morph at my local show and saves me the shipping and hassle. Me i prefer shows over online. But it comes down to knowing who attends ur shows and who u can "trust" there