"If there's time for you to go to bed at night, there's time for you to take an hour-long nap during your shift." It just doesn't follow.
Long Rests typically happen at the end of the day, while Short Rests happen during it. They don't happen at the same time. And just as importantly, LR resources tend to come in greater quantities than SR ones, so you don't run out of them at the same time either.