I'm fairly certain you can't return e-cig products that have already been used . . . so that solves that!
Money is always tough between couples - my wife gets on my case for my e-cig spending even though it's not that much and I make enough money to cover it. She doesn't even work yet I don't monitor her spending .. which is plenty, believe me. I think it's more her getting annoyed seeing me vaping all the time - so she complains whenever vape mail arrives.
The greatest marriage skill I've learned is the ability to tune absolutely anything out. "What! Another e-cig package? blah blah blah".
That is precisely the reason that all of my Vape Mail gets sent to my office.