To start with Mitch's question, if his observation is true, the answer is ignorance on the part of the seller. There are also lots of FFL holders who "know" lots of wrong things about the BATF rules. Like insisting that a gun they are receiving for transfer from another state come from an FFL holder. Not so. But there are some who insist on it. My local FFL holder insists that I can sell to, or buy from a private party in another state without using an FFL holder on the receiving end. Wrong again! He also believes if the gun comes from a dealer in another state, he needs that dealer's FFL copy. Wrong again.
Every time someone asks a question regarding FFL, BATF rules or C&R procedures here, instead of going to the website and finding out for himself, as he should, he'll get six different answers to his question. At least 5 of them have to be wrong, maybe all six.
As Chuck, who has a C&R license and considerable experience with it said, throwing hearsay information into the mix only muddies the water.
Go to the websites and read for yourself. Don't take the lazy way out and rely on others who may know even less than you about the subject.