I would disagree on all your points, icecream is a product that can be made by one person or family and is often done so, even without the use of conventional appliances. People still travelled without roads, and it's easy enough to defend my property myself while doing my job. My current store was chosen for this exact reason, I can still supply icecream to a broken town, even if the dollar fails, obviously not in as large of quantity.
I up voted because I enjoy a good debate haha but I still think my job requires no intervention from any outside source to run. While currency is created by the same society that upholds the written laws, a batter system is just as sufficient.