I've seen staff, from at least one retailer, in the middle if summer, putting working fans in the dumpster and then beating them with hammers until destroyed. They needed more shelf space for AC units. The staff weren't happy doing it, but weren't given much choice about it.
Ultimately, what should retailers do with overstock? You'd hope they could sell it off cheap or donate it to a suitable charity, and I'm sure some percentage is, but it works against them as customers buy the discounted items rather than the higher profit ones. The retailers don't want to destroy stock as it's lost profit, but it's the most economical path for them to take in that situation. I suspect it'll take a change in regulations to change that arithmetic.