I'm not surprised at this at all. Growing up on the farm, half of our hogs' diet was made up of day old bread and expired milk-cheap feed since the only cost was hauling it away. The cows loved the bread, we'd feed them a loaf as a treat every now and then, they'd almost go crazy for it once they got a taste of it.
The oddest though, there is an ice cream plant in the area and all their waste ice cream goes to several local hog farmers in the area for feed.