in my experiences in a couple of places it was usually from recurring trips to downtown areas to bars, restaurants, etc. so after chatting a bit a business card

in my experiences in a couple of places it was usually from recurring trips to downtown areas to bars, restaurants, etc. so after chatting a bit a business card was offered or just a hey here's my cell call anytime you want a ride and i think the direct relationship was good for both parties though of course sometimes the driver wouldn't be available and maybe my saying "common" is overstating it since my knowledge is ultimately quite limited compared to the universe of taxi/rider trips taken but I and a handful or friends/acquaintances over the years have had these (ultimately fleeting) taxi relationships which were generally pleasant while they lasted