Ballpits are a bad idea. Ive operated them, and I was so glad when the company got rid of them. And, mine were nothing of that scope and scale.
Neat idea, operational and guest safety nightmare. Yes, safety, cause things get dropped in there. Hazardous things Ive found cleaning out ball pits range from knives and syringes to used condoms.
I had all the floors in my house replaced with ballpits a few years ago. I concur. Bad idea.