$7 each may be what they sell them for on airplanes, but you can buy them for around a dollar in many stores and wholesale they cost a fraction of a dollar. How do I know? I have strange hobbies and while I traveled all over this country in my job I would buy mini-bottles whenever I found a good deal. I have about 15,000 bottles of all kinds and never paid more than $1.25 for any of them, and I never bought anything less than top shelf booze. What can I say? We all do some crazy things.
Interesting :-) I bet they hold their value better than paper dollars too!