I find it's easier to convince the wife that having a large gameroom is a good idea when you don't go out of pocket for any of it. I've been funding my game room through a side biz of buying, selling, trading, etc... Not just arcade related stuff, but vintage consoles, Legos, etc...
After 2 years of doing that I have just under 20 working video games (including parts to restore them all) and a HUO LOTR Pin. I track it all in a Paypal account so I'm never pulling from the bank accounts. My wife honestly doesn't care, but it's always nice to take a potential argument starter off the table lol...