City also have a scheme were if you notify them that you are not able to attend a game, they will sell it on for you and if sold they then knock the value off your next seasons card price. Think you are only allowed to sell it this way 6 times.Yes other people can use it, but if they are caught doing something against stadium regulations (eg smoking) then your card will be suspended
As for the value (lucky dip) card, you could be located anywhere, from the worst seat to one of the best. They are used to fill the single seats dotted around and it purely is luck on where you are allocated