Johnnie
I think it gets down to how much load and how big the contractor generators are when you start talking about "loudness". I just a purchased a Champion inverter-generator which is a Chinese knock-0ff of the Hondas and yamahas. I've only run mine with very little load on it. Yes- it gets louder when there is a load and I do not have a contractor generator to do a side by side comparison with. That said- under load it is not as loud as "some" generators I have heard in campgrounds. That said- I can't tell you how big 'those' generators were. They could well have been 5500 or 7500 watts or bigger.
I plan to use my generator to top off the batteries if need be. I carry an 18 watt solar panel.....and if I am judicious it helps replace my daily (nightly) electrical useage . With 200 amp hours of battery storeage and 200 watts of solar- if done right, you should be in good shape 90 % of the time. I think the issues are folks who use them(generators) to run AC 24/7 and toasters in the morning etc and those loads tends to require increased out put.
I have my dinky little panel set up to move around the campsite to capture optimal sunlight during the day. If you do something like that- are judicious with the use of lighting and your fan- you should be great. I use 9 volt electric lanterns and d cell operated portable fans to move the air if I am worried about running out of juice and I rarely have hook-ups. And, my two batterys total about 120 amphrs. Otherwise- if I don't run it all day- my capacity is good for my fantastic fan, as well.
Depending on how much "load" my batterycharger/converter uses- my guess is I might be able to stay in "eco" mode when charging my batterys and, thus, keep the noise pretty low for a couple of hours a day. "jack and Janet" on this forum has a 1000 watt Honda he uses in this manner and he can probably offer more insight on how loud his gets.
There are a number of good books on 12 volt systems and I suggest you grab one. One I have used is "The complete book of boon docking" by Bill Moeler, and they have a great couple chapters on 12 volt life.
I think you will find your set-up will be more than enough and not require much generator charging unless you are staying for extended periods of time. That said, and getting back to your original question, "YES" there isn't any reason to run a generator if won't have some type of load on it. However,the size of the load will impact the "loudness" and in some cases, the inverter type generators can stay quieter under a lighter load.
Good Camping
Merry Christmas
Rick