I use small haylage nets (£4 each) (or a large one flopped over the hurdle between two pens). Safe enough as long as you keep them filled up. Wouldn't pay £20 a pop for hay racks, i agree they are too high - ok if you have big sheep I suppose. I'd also use feed bags too, although they are more time consuming to tie up than the haylage nets.
Do I recall someone mentioning using shopping baskets previously?? You could hook them up with some sort of hinge going on, and you would be able to place them lower than the hook over type hay rack.