As Vall says, it's a double-edged sword, and it is up to the buyer to look carefully at photos and ask questions to find the hidden bargains, and reject the guns that are over-priced or have undisclosed defects.
It will remain that way until someone comes up with a firearms version of CarFax.
I recently got a really good buy on a Lefever G grade double that was advertised as a 12 gauge. I suspected it might shrink during shipping, and sure enough, it turned into a 16 gauge. I'm certainly not complaining.
