I find it strange that most likely the very people complaining about the "noise" from model aircraft probably use a device to mow their grass that is considerably "noisier".
Noise is one of the major contributors to the loss of many a fine flying sites, but an issue that can be dealt with and overcome.
When was the last time you were in your car, waiting at a stop light, and somone several cars back had their sound system cranked to the extent that it caused the rear view mirror in your car to vibrate? Just ain't fair, is it?
I guess noise is noise but the noise of a good running four stroke is music to my ears. The music that makes my rear view mirror vibrate, well, that's just plain noise.