My wife is supportive of my hobby, but it wasn't always that way. We've been married for 25yrs. now, and for a long time when I made some extra money, she would say that's your money buy something you want with it. Then, when I did or if I told her what I was going to buy she would say why are you getting that or why do you need that. Now we have separate savings accounts. I buy what I want from mine and she buys what she want from hers. Bonus is she doesn't find out what I'm getting her for x-mas or birthdays and such because she doesn't get the statements from my account.
And these days she usually asks what I'm doing to customize my stuff rather than why I need it.