TIFU by buying a bean bag chair for my wife

Today, my 4 mo pregnant wife told me she wanted a bean bag chair so she could have somewhere to sit in my office, especially when our child is born in October. There was one that her best friend has that she really liked and wanted to get the same one, but it was a little more expensive than usual. No problem, but I should have known since it was her better-off friend that likes to be a bit bougie sometimes. It was a $350 one off of Pottery Barn. We live paycheck to paycheck so this was a bit steep for us, especially with a baby on the way. I told her we could do it if we call this her birthday, Christmas, and anniversary gift and I won't really get her anything else for those days.

My FU: Her response was that we could also consider this her "push gift", but in return she would still like me to do something else on those days. My dumb-ass said "Your what?" with the gusto of someone who had just been cut in line. She proceded to tell me that it was now becoming a thing to buy a "push gift" for the partner giving birth to the baby.

Since I am a well-trained spouse, I held back my immediate and somewhat rude reaction of chuckling at the idea and instead sarcastically responded with something that would make you completely doubt my training. "So me taking care of you hand and foot for the couple weeks after the birth while you are essentially bedridden aren't enough for you? I have to buy you a gift on top of that?" Queue one enraged wife at the beginning of her second trimester.

I eventually calmed her down but she is still obviously pissed because of this. Could I have handled it better? Sure, but I thought she was joking about what a push gift was. I had already moved heaven and earth so that I could actually take 4 weeks paid leave after the birth (US company with less than 50 people, so I am not guaranteed even unpaid parental leave). I wasn't expecting her to actually be serious about wanting a gift from me for something she wanted to do in the first place.

TL;DR: while buying an expensive beanbag chair for my pregnant wife in exchange for multiple holiday gifts over the next year: I learned what a push gift was, that I no longer needed to look for one, and pissed her off because I wasn't going to get her one in the first place (because I had never heard of them).

Edit: her family is providing a lot of hand-me-downs since she has several older cousins who are done with having kids. The baby stuff isn't a huge concern for us financially, mostly just the medical bills need to be addressed.