No, it wouldn't be that hard, but I have the cash, they have the firearm I paid for already, and I want both firearms now. It's a legal transaction. That's the part that gets under my skin.
As a former dealer, I can say that filling out a piece of paperwork is not the limit of the duties the dealer has to go through. First, they have to field the phone call and deal with the person wanting the gun. Then they have to fax or mail their FFL to the sending dealer. They may or may not have to speak to the other dealer. Then they generally field two or three "Is it there yet?" calls from the buyer. Finally, when it comes in, they have to accept it and sign for it, unpackage it, log it in, call you and leave a message, field a call when you ask what their hours are, help you when you get there, call in NICS, fill out the paperwork, call the dealer that sent you the gun to tell them the serial # was wrong on the gun, then stand and listen to you BS about how your grandpappy knew Carbine Williams and thought he was a jerk. Really, it's more time and work than just filling out a piece of paper.
Then again, I now have to make a return trip and fill out ANOTHER 4473. I'd have thought that the time saved in paperwork and not having me in the shop again would be enough to make up for the 15-20 minutes needed to complete and main the multiple sales forms.