Just as a simple example, we own farm land ~ 200 miles away, and a family member cuts hay on it. In theory, we own 40% of the hay cut on our portion of the land.
Every single year when I get ready to buy hay for the winter, we sit down and cost it out. Every year, it's been cheaper to buy hay locally than it would be to take a truck and flat bed ~200 miles and pick up FREE hay. That was true when diesel was $3./gallon, even more true now when it's $4./gallon. We've also never factored our time into the equation, as we'd make a family visit out of the trip.
A barn owner would have to factor in the cost of their time to travel to pick up the hay, it's time they're not feeding, mucking, mowing, dragging the arena, etc.
So I am really intrigued by this magical idea you can somehow avoid high hay prices by driving out of the area. Even if square bales were $10 locally and $4 4 hours a way, time and fuel costs make it a wash.
I'd also like to point out that a lot of options for alternate forage that work for a 1 - 3 horse home operation (slow feed nets, soaking hay cubes, etc.) may not feasible for a large commercial barn.