You don't have to be 18 to buy it. Its legal as insence, if someone tells you, you gotta be 18 to buy it, they are fucking dumb. Yeah, we know what its used for, but you don't gotta be 18 to buy insence, and if they say you do, they're admitting its not insence.

Just go in there and if they ask for you to be 18, be like "...Its insence. You don't have to be 18 to buy insence" and try to buy that, and some other insence to prove your point. Just give 'em a hard time. Thats like trying to sell someone mountain dew but saying "hey you gotta be 18"