I've never driven a metered cab, and I drove cab for 21 years. Do I know how they work? Yes. When I was first learning the business, did I think it would be much easier to drive a metered cab? Yes.
Driving a metered cab should be easy. You turn on the meter, put the cab in drive, and away you go. When more than one passenger is in the cab, it gets complicated for the passengers and the driver.
Meters assume a single passenger. Ban the practice of taking multiple passengers, and you will go a long way to insuring nobody ever gets ripped off. A meter can't prevent the driver from taking the scenic route, but getting a receipt for the ride allows the passenger to call the company and see if the fare was reasonable. The company will tell you the truth, they don't want their drivers ripping off the public, and they will fire a driver for doing it.
How does a non metered cab work? Simple, you pay for the ride from point A to point B, no matter what route is taken.
How does it work when a metered cab takes multiple passengers? Good question. There is going to be a policy that will cover that, but it's open a lot of abuse. The Albany, New York area airport has a policy to cover that, but is it followed, so the customers get charged fairly? Probably not. Why? Airport people are frequently visitors. The cab driver casually asks the 2 passengers going to different locations if it is their first time visiting Albany, New York. They say yes. They just told that cab driver he can rip them off for as much as he thinks he can get away with, if he's a crook.
If those passengers ask for separate receipts, which they need for their expenses, they are going to get charged for the maximum amount of money the driver can rationalize. They wanted receipts, and they got them, and those little pieces of paper cost them a small fortune. The most honest, god fearing driver I've ever met, considers receipts the threshold, if you need a receipt, you pay full fare. He drives a metered cab, so that full fare receipt is an expensive full fare. Will his company back him up? Yes. Technically, he's done nothing wrong. Moral of the story? If you are sharing a ride with another business man, flip a coin to decide who pays and gets the receipt. Let the other fellow give you a 10 spot out of his petty cash.