It must be nice to be able to casually promise small things and not have your kid hold you to it

At my daughter's best friends party today, there was a slash pad and a big playground. Host parents tell their daughter no playground until after food, cake, and piñata, because it's large, and they don't want to have to wrangle everyone back for these things. This is reasonable enough, the parents all agree.

Except after these things are done, they tell their daughter still no playground. It has been 2.5 hours since the party started, and it is July in Florida. It is hot, these kids can't last all day. I finally take my daughter to the playground, to keep my promise.

I'm slightly jealous that their kid just went back to the splash pad, because mine would have gotten very upset and tell me that I had promised they could do the playground. I would have needed a real reason, there would be a whole negotiation.

I do in a way feel bad for their kid though, as easy going kids don't always get promises made to them kept.

Any else's kid like mine, and hold them to every small thing they've agreed to?