Mustang Hindrocket

H.R. 1018 is the "Restore Our American Mustangs Act." It can fairly be described as a welfare program for horses. Believe it or not--this isn't satire--here is what the bill will do:

Establishes an additional 19 million acres of public and private land for wild horses
Nineteen million acres, by the way, is around 28 times the area of Rhode Island. If you think Rhode Island is too small to worry about, it's also more than a third of the state of Minnesota.
Well, aren't we glad that they're not transporting all those horses to Minnesota for protection, then!

Here's the other side:
Congress originally passed the Wild Free-Roaming Horse and Burro Act in 1971 to protect our wild horses, but in 2004 this protection was gutted in a midnight maneuver by then-Senator Conrad Burns (R-Mont.). Then the federal Bureau of Land Management said it would consider killing more than 30,000 horses in holding pens.
I never fully understood why it was necessary to stop protection of the horses--outside of the fact that ecologically speaking they're an invasive species. As far as I understand it, most horses hang out in open range land, land shared by cattle ranchers and other users. It's not like they're setting aside 19 million acres and disallowing any other use of the land; they're just saying that within those 19 million acres they'll practice some form of animal control and no one is allowed to kill horses there. Like with many things from the early 2000's this makes sense only in light of thinking that they overturned the mustang protections in a vain attempt to piss off liberals. Am I missing something?