Freenow's trick or genius has been to convince the punters that the FN app is the only way to get a taxi these days. When the 'there's no taxis' stories appear in the papers nowadays, it's usually a variation of, "I was standing outside the pub with 50 other people pressing the app and no taxi turned up."
It would never occur to a lot of young people to stick their hand out or go to a rank.