Yeah man, a 1min 15 second race it totally killer. Couldn't possible have the energy left for 5 more seconds. It's not about the energy or fatigue, it's the decision of the athlete and they just don't seem to care.
Why do I care, I care because they are in the spot light representing the top level of the sport and it's embarrassing.
It's kinda like a baseball player walking off the field vs. running. Doesn't change the outcome of the game, but it reflects negatively on the sport.