You have your info on an open server on your network? You should be more worried about that than a charger.Because anyone with my password can access everything on my home network including personal and financial details.
Although my on-line banking etc. is further protected by its own PIN / password, all the statements etc. I have downloaded routinely are not.
A quick scan of my location shows all my neighbors have their WiFi password protected so I'm not unique in not handing out password to people/organisations I don't know/trust.
There is absolutely no reason to allow access to my personal data, my smart meter connects wireless to a dedicated network without need to access mine.