Presumably, if you are paying more, then part of that increased amount you are paying is to make certain that the portion of the grid needed to keep your factor

Presumably, if you are paying more, then part of that increased amount you are paying is to make certain that the portion of the grid needed to keep your factory going is properly maintained. Unlike the rest of the grid. Which would apparently be too expensive (i.e. everyone on the grid would need to pay the extra fees for increased uptime).