So while the driver doesn't
So while the driver doesn't have to pay for the electricity cost needed to charge his car - Tesla does since they're supplying the electricity. Plus, of course, what's his time worth? He gets to drive for 2 hours, and then stop for 30 minutes.
As a proof of concept it's noteworthy. As anything actually worth doing on a large commercial basis - especially since the average consumer (a) can't afford a Tesla and (b) doesn't have the time to waste - it's still worth noting but only as a stunt.
To quote an article headline from several years ago - "Electric cars are the next best thing ... and they always will be".