@NattlesNat i have a MIL who were like this. When dh & I first got together and had our first child, we were honestly quite young & broke.
MIL (tight but no money issues) made a big show & tell of displaying all the baby stuff she had bought (in hindsight, very basic purchases, think baby towel, vests, clothing only bought when on sale) whilst I stood there 2 days postpartum in pain. At the time, I felt they were being generous, but as I’ve gotten older… I see it in a very different light. It’s much more about her
Her need for praise, for the big thank yous, for the validation, for the attention.
If they had truly wanted to help us, she’d have given us something towards a big ticket item, like a car seat, pram, furniture. My parents put towards these, and what we couldn’t afford to buy in cash, we put on a cc. Nothing of any significant use or value came from my in-laws, but every small purchase from the likes of Tesco clothing sale had to be grandly acknowledged.
As the years have gone on, I just grey-rock her, “that’s nice, thanks” is all the input I give. She’s never stopped buying absolute crap that’s reduced in the sales to nothing (think plain summer shorts reduced to £1, when I’m buying uniforms, school shoes, school bags, etc, at the end of August) whereas my parents would have taken them to Tesco to buy the lunch boxes & stationery for the new term to actually lighten the load a bit. It’s never stopped, her need for the grand gesture of thanks have never stopped, I just stop giving her any of my headspace. She’s wasted so much money on pure nonsense over the years that has ultimately been thrown out. Buy cheap, buy twice…
People like this don’t really change, so just do what you can to not be disappointed or annoyed by it. I also used to send a lot of the crap toys back to their house, rather than them clutter up mine.