Really? I thought everybody rode a hoss at least once!
I mean, not everybody in the whole world, of course...but when I was a kid, the fifth-graders in our school district (and all the school districts around us) took a week-long sleepover camp field trip to a nature camp in Michigan, and one of the things we did there was hossback riding. It was just a thing everybody did once when we were young. I've been a few times since, but always on somebody's dime -- it was cool that our whole school got to do it once regardless of socioeconomic status (though we lived in a fairly upper-middle-class suburb anyhow).
I think nowadays, because of budget stuff, they do a series of day trips to a camp closer to home, but I'm guessing hossback riding is still involved. It was the highlight of the week when I was there.
I would suggest that you come visit me so I could take you riding at one of the local places that does that -- we have many -- but visiting Ash for that would be cooler.