A disagreement about a small expense may be carrying a larger worry about security.

An argument about a small purchase is rarely about the purchase. Small sums are where a bigger fear becomes sayable: that there is not enough, that the future is not safe, that one of you is steering somewhere the other did not agree to. The specific purchase is just the place the worry surfaced. Winning the argument about it settles nothing.

When money talk turns sharp over something minor, pause and ask what the worry underneath is. Say your own version first if it helps. The conversation you need is about the shape of the next year, not the receipt.