Discount Gun Sales Just not a good business practice Aloha , Oregon

I went into Discount Gun Sales on 185th in the Tanasbourne area to purchase gun. I was interested in a particular one. Had the sales rep show it to me. He said " Do you want to buy it?" I said yes. The next step was that he ran the entire cost of the piece on my credit card ( $298) and THEN he had me sign a statement saying that for whatever reason I was not approved to purchase gun, that they would keep 20%  "restocking fee" . Ran background check, did not get approved. I had know idea that I was not going to get approved to purchase gun. There was no restocking to do. The gun was on the wall, he took it off and showed it to me. All he had to do was walk over 10 feet, put gun back on wall.   I know for a fact that the process for  purchasing guns at other retail places does not go the way I experienced at this store. I have never had to forfeit a percentage of money just to request purchase of gun or any other item in Oregon.