I've name changed in case I am being totally unreasonable 
I sometimes let DS have a little go on those supermarket rides. You know the little cards or miniature roundabouts etc that you let children on?
Anyway, we have a Peppa Pig one near us. It technically fits two children but at a bit of a squeeze unless they're both small.
I popped £2 in and put toddler DS onto the ride. He was thrilled as usual as he likes the rides. Just before I pressed the start button, this mum comes up behind me and says "Go on then Lucas, quickly sit next to him and have a go too".
The child looked about 4/5 but of course you never know.
I was a bit surprised but smiled and acted like it wasn't anything to comment on. But then realised it is a bit cheeky, isn't it?
For clarification I know this isn't a major event, I'm just wondering if anyone else thinks it's quite rude. I say that because I certainly wouldn't do it to someone. I don't think I'd ask if they could join in on someone's ride either, especially a small one like that.
AIBU?
*The little boy wasn't actually called Lucas.