I avoid it at any cost, even when they're free, for example when public transportation has issues they offer free taxis to the affected passengers. I always opt out for walking, renting a bike, if it's close, or paying for an uber if it's a longer distance, rather than driving for free with the taxi.
The only advantage taxis had over uber is that there's more of them, and during some larger events such as Oktoberfest uber was always fully booked.
The regulation needs to be relaxed so that uber, and others, can compete based on their service - not some other rules and weird laws like the one mentioned in the article "that hired cars have to return to a rental firm’s main office after carrying out a ride,"