You might have a nice little chat with the ladies who work behind the counter before you decide to try this tactic. They're really generally pretty nice people who have kind of crappy jobs.

Wouldn't it be more efficient to pay the ticket with a check or ten-dollar bills, and then in the time you have remaining (that you would have spent standing there in the parking office, waiting for Dot to count your quarters) write your own letter to the mayor; rather than try to induce the people waiting behind you in line to do so?