(at least I haven't seen this brought up)
If Donald fails to report by Monday (Aug 8th, I believe), he will lose a year of his UFA eligibility. This means he would need to play another year before he becomes an Unrestricted Free Agent. Instead, next year he would become a Restricted Free Agent.
This is a HUGE deal, and much more significant than the $40,000/day fines.
Will be very interesting to see if his holdout can hold up another week.
As myself and others have stated (not to beat a dead horse), the Rams have significantly more leverage in this situation, and while I understand Donald's frustration with the Rookie pay scale, it's hard to see the wisdom in his decision.
I also think we shouldn't jump to the conclusion that Donald will behave like an upset diva if he doesn't get his way. He's a mature guy, and he understands the potential consequences of his decisions. This is just part of life in the NFL for a talent as rare as his.