Good point. For your example there are rules elsewhere. For bonding a water heater no one has found any rules elsewhere.
In your example the rules concerning small appliance 20amp circuits have phrases "SHALL BE PROVIDED FOR ALL" and "SHALL SERVE ALL" which sounds like they are there to prevent other options like additional 15amp circuits. The bonding section does not use the word "ALL" that I can find. Is there a rule elsewhere that covers it?
look at the post above yours and you will see "shall be bond TO" which implies that there is only one place that it is to be bonded TO