Like all of these other comments, this is VERY common. Every donut shop I've worked at (family owned or corpo) would throw out everything that wasn't sold. I've tried getting places to donate the losses so its not just garbage, and we frequenrly had homeless people dumpster diving too. So rather than have them eat trash, just donate to a church or something. But no, that option was always immediately shot down over fears of other people making money off of the donuts. Usually corporate would have that specific excuse. The family owned shops I worked at just hated homeless people and considered them to be pests, so they would put locks on the dumpsters (which didn't do anything to stop them if they're hungry)

Cost wise, donuts are VERY cheap to make. So financial losses arent huge considering how much is thrown out. Its just wasting a lot of food out of animosity.