A slow feeder might be something to check out. The hay is off the ground so horses don’t ingest sand. We bought the plans from this company:
My husband modified it and made two boxes (for use in two stalls) rather than one long one. (We have two horses). Our horses understood immediately how to use it. No hay waste. No sand worries. We don’t have super cold winters in the Pacific NW, so I don’t worry about their mouths on the wire grate. But I have seen pictures of the same wire grate with a coating of some kind. The video shows the woman fluffing the hay. I don’t fluff the hay. In fact, I stand it on end so it takes more time to get it out and keeps my gelding occupied a bit longer.