Phil's scenario - that would necessitate a generator run - is rather particular. Mostly, it was due to A/C. They tried to camp in the shade because it was too hot. In some places it's about the same hot and humid in the night as it is in daytime. Running A/C day and night (=running a generator) is not much fun, I don't think anybody will argue this.
"Properly installed" - I doubt it's even possible to install a generator in a class B or class C so that it wouldn't be irritating for both the owner and his neighbors. Unless it's hidden few hundred meters away in a concrete shack downwind, you will hear it and smell it and/or feel vibration through the frame.
