Gift card scams happens every hr all across the countrt. Biggest way to take a stolen CC number, buy gift cards, sale them for cash.
I can't speak to the Disney Gift card program and its benefits becuase I don't use it, but I'd like to provide some perspective as to why these stores are denying it and why different managers act different about some of the less typical behaviors.
It is definitely true that buying gift cards with stolen credit cards is a big scam. What's less obvious about these scams is that once the card is reported stolen, the purchaser who sold the cards are the ones who are out the money. These purchasers have different policies and implementations of those policies, and many of them involve reprimanding or even firing the employee who did the transaction or the manager on duty. And they can implement some controls in the computers to fight this, but done overzealously that's more likely to catch legit customers than scammers. In at least one store I worked in, we had a company that would only permit so many of its card to be sold per store per day, and would permit any subsequent transactions, but immediately cancel the card after payment was approved.
Target management's policy sounds like it uses human intervention to prevent scams. It sounds like it puts a lot of pressure on employees not to fall for them, so they probably get fired or disciplined for messing up. It sounds like computer controls on the cards are somewhat limited.
This doesn't make the lack of clarity on this stuff ok, but I hope it helps with your patience.
One thing to keep in mind with this is that the stolen card is not the only kind of credit card scam out there. There are scams that involve altering the cards and then waiting until they're activated to exhaust them, although that's far less common. So to a certain extent some of these policies don't just protect the store from liability, but the consumer. I'm not saying don't use whatever discounts you can get with these, but if you're not saving money on gift cards and you're not using them for gifts, it's often not the best choice to use them, especially if they aren't stored behind the counter.
I empathize with your frustration and I hope thinking about this from the retail perspective takes the edge off the frustration a little.