There are FAA regs that pertain to commercial use, and it will probably stay that way.. In the hobby world whatever rules apply to all other model aircraft also apply to multi-rotors. As far as them chasing alongside cars, it has been done for close to 15 mins out in the desert and probably 30-40 mph just for something to do. I missed NAB for the 1st time in around 30 years, the one time I had a full plate between multi-rotor and EAS meetings :(
PS-
HERE are the proposed FAA rules that are literally years behind the rest of the world.