Not really. Aircraft taxi in on their own power and keep them on if they are being connected to ground power. Plus, almost everyone uses their APU, which are also very loud.
|Quoting GentFromAlaska (Reply 2):|
Another thought would be to eliminate any flying debris which may get airborne by jet wash.
This is mostly the reason why. I've been blasted by the jet blast from aircraft turning into gates across the alleyway. Also, a recent incident where someone on a golf cart drove behind an aircraft at a gate with the engines still running, had the windshield blown all the way across the allyway. Luckily it didn't hit anyone. Plus, there is a road that crosses the opening of the alleyways. Again, I've driven along that road after an aircraft taxis into Gates 24 and 25 and still could feel the jet blast.
The only times an engine can be started at a gate or in the alleyway is if the aircraft needs an air start cart or for engine maintenance. And they need permission from ramp control in order to do it.