i think the OP has a point here. Teslas have a decent battery pack and rarely do we need to use Level 2 chargers. Holding a Level 2 charger and not charging just should not happen. If you don't need the charge then don't hold the spot. If you do hold the spot at least charge and give those other EV owners an option to contact you if they critically need to charge. It can be thru Plugshare our thru a note on you car or on the charge port. Evenex even has a laminated card you can use.
But as EV owners we should follow the basic rules of etiquette around charging. Plug in cars has a good article on etiquette.
Electric Vehicle Charging Etiquette | PluginCars.com
Keep in mind that over the next couple of years EV's are going to be more and more common on the road. Only the Tesla has the capability to quick charge to 80% in a timely manner. The new Leaf or the new Chevy bolt can only max out at about 70-80 miles on a quick charge (chadmo or SEA Combo). Those quick chargers are also limited to only 30 minutes so they will not have no option for a quick full charge anyway. The need for Level 2 chargers is only going to increase. Currently there are not enough chargers at popular locations for the amount of EV drivers on the road. Once the affordable 200 mile range cars start coming out the problem is only going to get worse. There is no incentive right now for more chargers to be put in place so expect things to get worse.
There already is a lot of hostility against Plug in hybrids & Tesla's using Level 2 spots. Don't be part of the problem because you have seen other idiots not follow etiquette.