Here’s how you won’t have to explain it, but be aware, if you don’t do it at the beginning of the relationship you’re probably never going to make it happen, especially if only one of you works/has income.
1) You both have your own bank accounts, checking or savings, bank or credit union, it doesn’t matter as long as they are separate.
2) You both fund a joint checking account for family expenditures like a home mortgage, utility bills, food, medical plan for the family, car payments, etc. The amount that goes into the joint account is negotiated every year in the first week of January, the amount can go up or down, but typically it will always go up, some years a little more than other years. One of you will probably fund the joint account more than the other, get over it, you’re in a relationship where give and take are mutually affirmed and for the good of the whole. I fund our joint account 2/3rds to my wife’s 1/3rd, I make more income than she does, I make it equitable AND so she has something left over, that’s a key part to this.
Note that I didn’t include retirement plans in #2, that’s because, typically, those plans should be done individually and through the employer so they can be funded with pre-tax dollars. And you’ll both need to fund these plans realistically to the best of your income ability.
3) After all the bills are paid and retirement plans funding set, maybe put something aside jointly for a nice vacation once or twice a year, what’s left over is yours individually to spend as you see fit and, here’s the best part, without having to ask permission or explain a purchase.
No cheating with the joint checking, food out with your buddies is on you, getting her nails done at the salon is on her...etc., etc..
You’ll still get some comments and looks about that $400 knife you bought, but it will be tempered because your spouse won’t know what you paid for it, unless you tell them...But that’s up to you...
This plan worked for my parents and it’s worked for my wife and I for 22-years, but neither of us are insecure, controlling types, if you or your spouse is this plan won’t work that well...
I commonly give the above info. out to young couples and/or newlyweds, the other thing I advise the newlyweds is to file their taxes separately, not jointly, this is all the better now under the new Federal tax plan.
Hope that helps...
It’s her thing. Cutting tools are my thing. We can afford it and it makes us happy. There really is no other explanation needed IMO. I mean, I don’t know why people collect knives myself. I see pictures of people’s collections covering a table top and I just ask...Why!?! 
