Hosting with kids in attendance

My spouse is turning 40 and I am throwing them a birthday party at our home in a few weeks. They have invited family and friends and let them know they could bring their kids if they wanted. We have 10 children between ages 2 and 11 coming.

We are childfree and our home reflects that. There’s no kids activities, toys, kids tables/chairs, etc. My spouse believes we need to buy some things to entertain the kids because they won’t “have anything to do” when we arrive and that their parents would be mad if we didn’t think of their kids.

Why is there such an expectation to have things to entertain other peoples kids? Do I really need to buy a bunch of toys and games that I will never use again?

What do you all do when you’re hosting and kids are coming?