Here, a lot of the places that board in a smaller way – places that won’t have websites or facebook pages, and are often only found through word of mouth or a bulletin board at a vet clinic, for instance – have always been family owned and run.
Typically, it’s a family with kids into horses, parents build a barn with several extra stalls, have an arena, maybe a round pen, possibly a jump course, pastures etc., and a small to moderate number of boarders. There might be a decent amount of land involved, too, as horses generally aren’t kept in small corral situations see in some areas.
I boarded at these types of facilities for most of the time back in my boarding days, rather than the big barns. Don’t think these places, or the horses kept there, get included in surveys, as I never heard about them (at this type of family place, I think I would have heard something over the years).
I personally never received one back then, even when I was boarding up to five horses, and haven’t received one here at our own place since we sold our broodmares. I can believe that there are fewer horses than before, but perhaps quite a few have fallen through the cracks, as well.