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I have not put myself on Plugshare, due to the parking situation in my location: I'm right by the hospital and we already have problems with people parking in the street rather than use the hospital carparks - my neighbours would probably be unhappy if I was seen to be offering a hospital parking facility for EVs!
Teslowjuice is a much more low-key thing and acknowledged to be for emergency use rather than routine parking, so I had less concern about that.