The difference is that it's impractical for Uber drivers to directly solicit customers, because too few ride at predictable times and places.
Handymen, cleaners, developers, hairdressers etc can (and do) establish relationships outside the "advertising platform" and can find a meaningful number of new clients (and total $) through word of mouth.
Handymen, cleaners, developers, hairdressers etc can (and do) establish relationships outside the "advertising platform" and can find a meaningful number of new clients (and total $) through word of mouth.