All too often fans seem to forget it's only a sport to us, for everyone directly involved it's a business. I've never begrudged any player in any sport using any legit leverage they have to improve their lot, business is busine$$. As an example is Kirk Cousins to blame for what owners have paid him? Hell no, good for him, he leveraged his position properly at every opportunity. I can hold him in contempt for whining about the position he put himself in by signing with Atlanta but that's hardly the same thing. He took their money, he takes what comes with it. The fundamentals of contractual employment are something the average fan hasn't got much experience with.
The CBA has hard and fast payroll slots for rookie draft picks, making how and if the payout happens the only real bone of contention in a rookie contract. As no position group is as unlikely to see a second contract as RB's it behooves them to be concerned with guarantees more than most. Again, it's just business and the factors inherent to that business.