[JRTJH]

Possibly carry a 20 pound tank in a plastic milk crate (to keep it from tipping over) as a "dire emergency only".... With 30 pound tanks, you'll have at least a couple of weeks in the summer and 2-3 days in the winter to get the empty tank refilled, and with the 20 pounder as an emergency only alternative, you'll always have another day or so "in the milk crate"....

Honestly, the only people I know of that run out of propane in the winter are those who just completely ignore checking their tanks. Most, after one of those events, will check tanks at least every other day for the rest of their camping life..... Those who run out in the summer, aren't affected by as much inconvenience (cooking over the campfire rather than on the built in grill), so they may not "learn the lesson the hard way as quickly"....