To buy MIL something different to what she's asked for?

[NoFucksImAQueen]

I know I am, I just want a moan really.
Every year for Christmas and birthdays she asks me what the kids like and i give her a big list of things yet she will go out and buy something completely different.
I.e. "What does x want?"
"Well he's into fireman sam, paw patrol and Thomas"
1 week later...
"I got x a robot car"

I wouldn't even care but why ask me?!

For ds1's birthday back in the summer I asked for cash, if it was ok, so we could buy him an annual pass for the zoo or similar to use over the summer holidays since he was having a party so would be getting lots of presents.
MIL said oh yes no problem, then bought him a present and said she would give him money at some point. As you can guess she never did. Which again would be fine but why bloody say you would, why say it was fine when I asked, why even say what a fab idea that is! . Arghhhh

Get her something different!

Can you get DP to answer this year and state no point giving ideas if she doesn't choose them? Word it along the lines of it's one of your child's top gifts and you don't want them to miss out so if she won't commit to it you can get someone else to get it?

Sorry I didn't realise anyone had replied. User it's already happened for this year that's why I posted. I told her ds2s favourite character right now and she got something totally unrelated. He'll still like it, he's 2 so he'll like anything but like I say it's just pointless her asking me.
I like her in every other way so it's almost harder to approach

Hmm I can see how annoying that is bit it could be worse. My mil just hands me the money and then expects to turn up on the occasion to hand over the present that I've picked, fetched and wrapped for her.