Because “Taxi driver and accomplice burgle homes of travelers” is a headline that goes back to the 1800s and the police know that this was a common thing. They would ask nicely then get a warrant if they had to (translation: Driver said no.).
Also, in certain cases, the driver for Uber or Lyft already agreed to surrender call and text histories to the company or to law enforcement in the event of an accident or criminal investigation related to the company. So no warrant may be required.
OK, I’ll take your word for it.
I’ve never used a taxi or these services for something like this (going on a trip), and never will - I have plenty of reliable people who’d do it instead. I guess some people have no choice.