Tow Straps
How else are you supposed to have tug-o-wars?
But seriously, tow straps are useful for a variety of reasons. Obviously, if you need to tow something, they’re pretty much indispensable but they’re also great for keeping things in the bed tied down. You should carry tow straps for the same reason any other workman carries rope. It’s a general purpose tool that weights very little, and can prove extremely useful.