The best case scenario is free choice hay, but not everyone has that option.
My horses are easy keepers, and only fed twice a day. If I didn't have to work I'd probably feed them smaller meals more often and keep hay in front of them at all times, but I don't have that luxury.
Are you boarding or do you have your horses at home? If you're boarding, you're not likely to convince a BO that they need to keep hay in front of your horses continuously, unless you're willing to pay extra for it.