As far as carrot and stick go its fairly crude.<p>A more "entertaining" way to punish parkers would be to log how much time they waste parking, provide a reasonable allowance (whatever, fifteen minutes per month will be waived) then refuse to start charging until the time is paid back. Or decelerate the fast charge to make up for the time. People in a hurry will not like it when they come back to their car in 30 minutes and its not begun charging.<p>Even more amusingly would be gamification playing into the well known range anxiety problem where every ten minutes the car sits there, its discharged back into the grid 5%.