Think about how ridiculous this plays out in everyday life.
"Dad, I was thinking about buying a pistol for self defense. I'd like to get a Glock, but I'm not making enough money at work to justify it. Do you think you and Mom could help me out for Christmas?"
"Son, we'd be happy to. That's a really wise decision, and now that you're 21, let's get you down to the courthouse and get you that carry permit." Your Mom and I will help you get the gun as an early Chrimstas gift, but we only had $250 set aside for your present, so the rest is your contribution. You can pay us back from your next paycheck."
Dad just described a felony.
Is this how we want our society to function?
And the situation you describe is actually exactly what transpired in this case if you think about it. The buyers "gift" happened to be the LE discount he was entitled to. Moral argument of his use of that discount not withstanding, that's why he purchased it and the uncle did not. Now you have to define what a "gift" legally is.