if they engage in the business of selling firearms....they are a dealer.
it doesnt matter what you call yourself.
thats like saying "oh im not a drug dealer, im just an unlicensed pharmacist".....
Dealer: as applied to a dealer in firearms, as defined in section 921(a)(11)(B), a person who devotes time, attention, and labor to engaging in such activity as a regular course of trade or business with the principal objective of livelihood and profit, but such term shall not include a person who makes occasional repairs of firearms, or who occasionally fits special barrels, stocks, or trigger mechanisms to firearms;
Can I buy a Barrett 50 Cal at a gun show in most states without filling out a 4473? Yes or no ? As a buyer I could give a flip what your dealer or seller status is. You can call yourself the tooth fairy for all I care. Fact remains is that there are still plenty of "sellers" out there who are actually dealers operating without a license.