This is the first I’ve heard of this and this was posted 2 YEARS ago! Talk about being late to the party. Oh well.
It’s long been a pretty well-kept secret, but the passengers on the Discovery Channel show aren’t just random travelers—they’re cast, just like actors or Oprah ultimate fans. The process has been detailed online, but here’s the gist: Riders are generally found or screened at a bar or on the street. People who are gregarious, funny, and sometimes half in the bag get told they’ve made it on a non-specified reality show and that a cab will be coming to take them to the shoot. A cab pulls up, and, surprise, it’s the Cash Cab! This might explain why so many improv-comedy types are on the show.