While it's always better to run them, I don't think not running necessarily causes any harm either. If you go to the southern Arizona area and look in larger RV storage lots, you'll see most of the license plates on the class As are not from Arizona. They belong to all of the snowbirds that come down for the winter. Some of them drive to particular RV park and then park them for the winter. Others (like us) get in them and go, never spending more than 3 - 4 nights all winter in the same area.
Unhook both sets of batteries when you park it for the winter, put them on a trickle charger if you can, winterize it and wait for next spring to roll around. Go for it.
Bill