Cars aren't that noisy, and drones are going to be high up in any case.

Cars don't have eight rotor blades slapping the air, and we've gotten pretty good at enclosing all the loud bits (on expensive cars). Noise would certainly be a problem for gas-powered drones.

And gas powered cars are a lot louder than electric cars.

To minimize noise and visual pollution, it would be better for these drones to fly low, along existing roads to take advantage of existing noise abatement measures (e.g. noise barriers walls, berms, roadside vegetation, etc.)