I think the point is she wanted to have a little fun with this, and seized the opportunity to be first to buy on the secondary market.
Don't over estimate the chances of getting a promo with a single pack anyway. I've been involved in a lot of these airdrops and trust me you feel really lucky if you get more than a guaranteed amount anyway. Clearly she won't get enough vouchers for even the minimum 50 packs. But there are other ways to take advantage of this airdrop.