Well, they were not forced to use leased land, they chose to in order to save money back in the day.
That is what many of the range wars were about. When the Homestead act was passed, many ranchers were already using that land (most often for free) without owning it. They resented homesteaders coming in since they would either have to pay the new owners, homestead the surrounding land themselves, or force them out.
Many made the choice to kill the homesteaders, so they didn’t have to pay taxes on the land.
Sorry, I have family that were involved in the range wars. While I have some sympathy for those ranchers caught in it today, it was a bad practice to start with.
The Feds own most of the west. 90% of a neighboring county is Fed land.
Individuals have no chance of ever even renting it from another private individual.
History is what it is.
Todays ranchers have the choice I outlined above.