Obviously I realize what the purpose for their policies is. However, in my situation, it turned out to be a major loss on their part. No one seems to be able to realize that age is rarely a measure of responsibility, but rather how long we've been in this world. On an average, maybe there is a correlation between age and responsibility, but this is just one of those things in which there are individuals that are very far away from the average, whether it be above or below. Also, its not only a question of responsibility, but knowledge, and there's plenty of smart, knowledgeable kids out there.
As one who really hates to see fish in an inhospitable environment, I can somewhat understand the reasons for this policy, and for me, it had never been too difficult just to come into the store with my mom or dad and get the fish with them, and it tended to work out just fine, since I needed them to give me a ride there anyway. However, the fact that all they go by is age is ridiculous. Many times at PetSmart, they won't question someone about the pet they are purchasing just because they are 18+, and therefore must have the "wisdom" to accommodate these fish. As an employee at an lfs, I tend to simply ask questions about their home aquariums in a non-accusatory manner regardless of age. If they speak with some know-how, then I don't see a need for quite so much questioning, and if they appear clueless, I avoid selling them anything live. That's how it should be.