A gun dealer has no need, nor any right to know what I plan to do with the gun I am purchasing, and I will refuse to give them any of that particular information. All the dealer has to be concerned with is: did I prove, according to the requirements of Federal and State laws, that I am who I am claiming to be and a resident of the state I am claiming to be a resident of. Do I pass the requirements of the background check required by Federal and State Laws. Is there anything I entered on the 4473 that will disqualify me from the purchase. Am I of legal age, according to Federal and State laws to purchase the firearm.
Anything beyond that, unless I disclose it voluntarily, is of no concern to the dealer, I will not disclose anything more than that to the dealer, and I would not do business with any dealer who expected anything more than that.
The bottom line is this: I am the purchaser of this firearm. I am legal to purchase this firearm. Once I purchase this firearm it is mine to legally dispose of it as I see fit. I can take this firearm out and shoot it the same day that I buy it, don't like it, sell it someone else, all on the same day. Or I can take this firearm out of the store and someone sees me walking on the sidewalk with it, says nice gun, I say you want to buy it, sure, there you go (as long as the person buying it is legal). I am the legal purchaser of the firearm and I can do with it as I please and selling it to my friend when he returns from overseas is a perfectly legal thing to do with it.