Higher prices for faster service is just the nature of any professional services business. Look at PCB fab and assembly there is a premium paid for shorter lead times. Likewise if call out a plumber or locksmith or whatever in the middle of the night it is going to be more expensive than if you can wait until the next business day.

Granted the tactic of quoting a very cheap price like in the story and then charging substantially higher on the spot is not ethical but I would be suspicious for any on demand professional service that responds immediately and quotes a low price.