I'm surprisingly tight when it comes to spending money on myself and my wife of 41 years is the same way. When I see a new pipe I want, I usually just tell her to take the money that she would spend on my birthday, Father's Day, Anniversary, etc., and save it until there is enough to buy the pipe I want or one like it. Mostly I keep my PAD under control by searching the local antique shops and collectible stores for estate pipes.
I do have to hide new tobacco purchases from her occasionally because I have a terrible time with TAD - Oh! Look dear!, The Country Squire just sent me a couple of samples of some of their blends!