If you have one at work, how does it work? At work, there's a fancy looking post with 4 outlets. One would bring one's own charging cable and hook it up to the car after plugging into the plug
Is it free? It's free for me but depends on where you work. I have seen charging stations at other offices that use blink which I think requires a monthly subscription. Nissan usually has a couple free charging stations in their lot. Also around me, Kohl's has a few free ones.
If it takes 30 min or so to charge your car, are you expected to move it rather quickly so others can plug in? Yes. Move it when you can. Since our office provides free outlets, they are not the fancy fast changing ones but rather the super slow 110. I move the car at lunchtime when the battery reaches about 80% charge to leave room for others. On occasion when I get to the office late, all the outlets are in use and I park elsewhere. When I return during lunch time, several spots open and that is very much appreciated.
What's appropriate car charging etiquette on the shared use car charging station? Move your car when it is adequately charged. If you haven't already, I would suggest that you read up on how to extend your battery life. Apparently it is not good for the battery to be or remain fully charged.
A major annoyance will be when you are ICE'ed... meaning a car with an internal combustible engine has parked in the clearly designated EV spot.
Seems like it would be easier to just walk around the garage or lot and see what the charging station looks like rather than trying to ask work. Non EV users are generally totally clueless about EV questions. If you happen to catch an EV user parking or leaving, that person will be the best person to get all the information you need. EV users are generally very friendly and enthusiastic about their car. I have gotten wonderful tips, like when is the best time to come, where there's a secret plug, etc.
Also apps like Plugshare are helpful. It's like a yelp for ev charging stations. Includes information like where are stations around you, whether or not they are free, how reliable they are.