I bet you'd still be able to do this in a local municipal biogas plant more efficiently. It would also scale better should you wish to run more than several mopeds like this.
Again, that’s centralized. Less central than your previous example, but still requires a dependency on their municipal plant and power lines. Not sure why this is a confusing concept.
The concept is not at all confusing, it's just useless. For load balancing, efficiency, and reliability reasons, a microgrid is more desirable than isolated households in pretty much all circumstances.