If they're making actual yeast dough balls you can't make that to order. You need to prep them and put them in the fridge and if the proof time is too long then they go in the dumpster. If they were hoping for a rush and didn't get it for whatever reason that could be a lot of dough balls. And when we're talking about one of the cheapest inputs in the whole system, doing too much prep is much preferable to doing not enough. Losing a $10-$20 pizza sale because you were worried about a 20 cent waste product is poor business.

Chains will usually ship the dough frozen from a central location, you then defrost it the night before you want to serve it. That means you need to project your sales for the next night otherwise it'll go bad. If you get it majorly wrong you'll be left with a load of dough that is bad

Bottom right is Peppes pizza. The bases come pre-sauced and frozen in packs of 20. You put them into an oiled pan and put racks of these pans into a leavening cupboard. They puff up a lot, but they need to be used the same day. Because they fall pretty quickly.

My guess is that they accidentally dropped a couple of boxes down the stairs and shattered them to the point they couldn't be used. Tossed them into the bin without thinking and the midday sun took care of the rest.

Similarly with chain pizza places like PJ's, the dough is made at a central location and distributed by truck twice a week. It's kept refrigerated for a while but it needs to be taken out of the fridge to rise. Sometimes franchises will order too much and it develops a black marbling of dead yeast, when it gets old. Can't sell it at that point so you toss it in the bin.

In short it's a failure of capitalism.

Ya, I was thinking maybe a power outage/fridge failure cause a whole fridge worth to need to be tossed at once, but most pizza shops are gonna try to toss as little dough as possible.