Is it good business for NB to offer $125K with no reductions to someone like Berian? Maybe, maybe not. A contract with no reductions is certainly a gamble for a shoe company. Perhaps certain Olympic champions have gotten such contracts, even from Nike, because their marketing value can last for many years after they have retired from competition, e.g. Sebastian Coe, and perhaps some sprinters and decathlon champions.
But someone new on the scene, even if they have a few outstanding marks, is somewhat of a gamble when you're writing a contract of 3 to 5 years. Reductions make sense from the sponsor's standpoint, and if the athlete demands no reductions, then I would think that the base pay offered would be far less. This ain't ball sports! The public's desire to follow T&F athletes is simply not as high as it is for ball sports players.
I don't blame athletes for trying to get the most advantageous deal for themselves, but if they can't get a contract without reductions, then they should understand that this is the way of the world; if your work declines in value, your pay gets reduced. But some people in Boulder and Bend think that they should keep getting paid the big bucks they once got when they were near the top.