The most Western place I encountered this was West Belfast, twenty years ago. This was after the peace agreement but before public transport had been fully restored. So there were London-style black taxis in certain areas that operated on a shared fee basis; no meter, you'd get in and agree a price, and there might be other people in there going the same way.
Important to note that this was fully private and unregulated.
gypsy cabs are also a negative externality particularly with unscrupulous actors
Petit cabs in Casablanca work this way, shared fee. I was only there for a few days so I couldn't make out how the metered fare was split fairly and didn't speak Arabic or French, so I usually just held out my hand full of coins and let the driver take what he wanted :^)