Wife and kids will all melt down if you say no. The last meltdown ruined a weekend.
The purchase isn’t that big a deal. But it’ll make other important bills late. But if you say yes, it’ll encourage the behavior. But you will also have a few days of peace.
Knowing the right thing to do, and having the energy and will power to follow through are very different things.
A) You can do what you think is right
B) You can do what other person thinks is right
It's not clear that either A or B is the correct choice.
It's not a gendered problem, although of course it looks like it when the other half of the couple is demanding The Thing and you're the one saying "no".
Or vice versa.
Some actions are strategic, and some are whimsical.
Whimsy is welcome and enjoyable when there are no strategic consequences, but not such a good idea when the consequences are obvious, predictable, and negative.
It really depends on whose non essential wishes are getting more funds in familly overall, whether there would be a strategic problem and so on.
But if your partner is annoyed so much over how money are spend, something is very wrong. Because regardless of who is right or whether split is fair, you are building long term ressentment problem. The attitude of "I get to have last word them partner not liking it is childish meltdown" destroys relationships.