I would buy it if I wanted and expect my husband to do the same, how does one even know what the other needs? However, there is a big difference (to me) between a 'want' and a 'need', and financial stress makes it more difficult to sustain a marriage. I would hope that I had a spouse who was happy that I could get what I wanted, and me the same for them- the things that make them happy. That being said however, though I am single I watched my parents (both working) without that much money, and know my mom spent near-to nothing on herself, to reduce the burden on my dad of working away in isolation, and my dad similarly spent very little, affording everything to my mom and us kids. So ultimately their concern for each other and us ended up with them being able to have saved $/ survived. But then I remember hearing my dad bought my mom a car (for her birthday), and always remembered my mom buying (or trying to) my dad the things he would love but wouldn't buy because he saved it for "us". I think that mutual concern/ continuing to work together with the same goals/ similarities in that, helped their marriage. And they were both hugely generous people. They never scrimped towards each other, either.
I think for a couple, respect and concern for what each person values/ would want to spend their money on is really the key, to want each other to be happy and do/ have what they enjoy, whatever that may be.
I don't think/ know if my dad always would have always agreed with what/ how much my mom gave, but he loved her for it because that was "her", said so, and he never begrudged it or interfered. It was the same for my mom, re: my dad.