I can tell you from my own experience that your system not only will not work, but it will cause lots of extra headaches in the process.
My ex employer had an "accountability system" set up for broken tools and equipment. My question to you is this: If one of your guys breaks a shovel because of neglect and nobody sees him, will he tell the truth? In my experience, the answer in most cases is no. Especially if you have an amigo with no money already or an american that likes to drink or smoke in his free time.
My next question is this: How do you figure out if that shovel was broken from neglect or accidentally?
You can't make an irresponsible person responsible by throwing money at them. You can't make them show up to work on time either.