“It’s hard to understand why someone from Chicago who is renting a car in Boston should be paying for police training in Massachusetts, but in a way that’s the genius of the proposal. A good share of rental car customers are from out of town, so hitting them with an extra fee doesn’t create a lot of pushback locally. … ‘That money could certainly be put to good use,’ Kyes says. ‘It’s a win-win for everybody.’ …”