Anyone who operates in an underhanded matter isn't promoting the sport, they're promoting their bank book, and can you trust some one who will break every rule to put money in their pocket?
If you get screwed from a retailer who's not on the retailers list or is not an active member of the forums (spamming doesn't count as active) there's very little we at ASC can do other then say what a bad person he is. At least with the retailers that are involved in the sport/listed on the forums there's something for them to lose.
Selling to minors can put a retailer in hot water depending on where the minor is as selling/giving a minor a gun is illegal in parts of Canada. Do you want to get screwed over because said retailer got stung by selling a minor a gun?