In the beginning
Reading through the first paragraph, where it states that no federal land grants were involved with the Great Northern Railway, it all sounds great.
But wait, I keep reading, and there's this:
On September 18, 1889, Hill changed the name of the Minneapolis and St. Cloud Railway (a railroad which existed primarily on paper, but which held very extensive land grants throughout the Midwest and Pacific Northwest) to the Great Northern Railway.
So, they bought the rights to the grants from someone who got them from Uncle Sam. Not uncommon at the time. Hearst did that in the Black Hills and created a company that exists today. More than one. Cattle barons of New Mexico used fake homesteaders to build enormous properties. They'd buy out, or drive out, the original homesteaders to expand their empires.
In my opinion, it's the same thing. Uncle Sam got the ball rolling by giving something to private industry.