IMO it could be much simpler than this. An old-school cordon that needs to be removed manually, would do the job just fine. No keys and no homelink necessary. For one, people are too lazy to get out of their cars before parking. And second, removing the cordon before parking in a space where you must not park, makes the violation much more obvious (to bystanders and to their own conscience).
There is one airport park and ride that does that in Atlanta. Sad thing is that EVs/Volts forget to replace the cones when they leave. Also too lazy.