Reddog.
ad 1 don't know about all states, but good luck researching the subject
2 on duallies you can install chains on inner, or outer tires
3. same
4. I've been active skier, going to Sierra 10 times a year and snow storm happen average 3-5 times a year, so it is not a big deal to wait them out. I had to put chains on the car about once a year.
Than the timing in unpredictable. California made requirement for commercial truck to carry chains in Sierra year around. You just never know.
The states we discuss here make it clear that cables and chains are equal options.
Years ago, driving El Camino I was pulling small car on dolly from Truckee going back to Bay Area.
Had cables and driving on the snow left from day before. Made it about 1/3 of the grade and cables were just not adequate.
Had to leave the dolly on the side of the road and go back to Truckee to pay arm for real chains.
Not likely the situation you will ever face with 4WD truck/camper/