Why didn't you tell her what you were going to use it for? I explained exactly what I was going to be doing with it, which then made the "See you in 500 years!" joke something that she understood completely.
I'm paranoid like that. I didn't want bells to go off and have them start requiring a hair beautification license to purchase more than 3' of it at 2.00 a foot. It's gonna happen. You heard it here first!