Winter camping is the best IMHO - it's often very quiet, and little crowds depending where you go.
just takes preparation and more money for fuel.
late December in Capitol Reef NP, it was down in the teens at night, 20s during the day. I was the only one in the campground. Asked the ranger if I could ignore generator hours to keep my heat on - they said no problem! So little blue ran pretty much all night keeping my plumbing heat and tank heaters on, and recharge batteries from the propane blower furnace, which was running more often than not. Same deal at Natural Bridges. Little blue ran all day and most of the night... Woke in the morning and it was buried under over a foot of fresh snow. Refilled with gas and it started right up.