The fact is there are plenty of parents and 18+ verified people out there who will and do lie. So even if you do ask every single person if they are buying for a minor, you still dont know 100% for sure.
A while ago I was talking to a friend who was complaining that she had welts all over her back. when I asked her about how it happened, she said her guy friend had shot her in the back with an airsoft shotgun in his living room from only a few feet away. I later found out that this kid, who was still only 14 at the time, had gotten his dad to go out and buy him an M3 shorty so he could shoot squirrels in the backyard. He then broke the shorty because he was racking on it too hard and tried to take it back for a full refund even though he had had it for at least a good six months already.
Just a story I thought I'd bitch about...
"It's not the size of the dog in the fight, it's the size of the fight in the dog."