I would think the competition/monopoly point gives a good reason for why this idea of 'who uses it' shouldn't apply to say 'hamburger restaurant'
If a hamburger restaurant starts doubling their prices the public can easily have another option. If the subway system in a city instantly doubled it's cost people would be hard pressed to suddenly find a new way to commute to work which is a necessity.
If a hamburger restaurant starts doubling their prices the public can easily have another option. If the subway system in a city instantly doubled it's cost people would be hard pressed to suddenly find a new way to commute to work which is a necessity.