When the power is out in our neighborhood, basically everyone runs their generators all night. They vary greatly in loudness, but our houses are far enough apart that it is not much of an issue... If you come home from an outing and it is quiet, you know that the power is back on. Most people have gas furnaces that could probably use an inverter and a couple of golf cart batteries to keep them going overnight, and I have confirmed that the setup in our van is capable of keeping our gas furnace running. I don't know anyone who does that in our neighborhood. Most people's furnaces are sized so that it takes quite a while to get their houses warm again in the winter if their heat has been off all night.
Inverter generators are much quieter, more efficient and you can hook them together so they can sync, but they cost several times as much and their ability to start an electric motor is typically not nearly as great.
I don’t mind loud generators when the power is out in the neighborhood. It’s when I’m up in the mountains, enjoying peace and quiet in the wilderness. Fortunately most campers that use portable generators seem to have inverter units now, and even those are typically shut off by 10 or 11 at night.