I never read anything so funny as this thread, Tell me you're all kidding, please.
I only been married for 25 years but I think its about 'trust'. ; My wife 'trusts' me enough that if I or we need a new car even, I go and buy it , a new TV , I go and buy it, a new house , I go and buy it,...... well ok we have a thing about houses she does come and help out on that one.
The point is , she trusts me to spend our money , same as I trust her to spend it , I never question her on a decision she makes and she never questions me, we respect each others ability to make informed decisions and know what will be best for ourselves and each other.
If it ever got to the point where we had to 'discuss' a purchase , I think I'd turn to hard liquer, and the girl probably would too.