underground can get depressing, light rail gives you the advantage of seeing the neighbour/traffic/sights without out the traffic getting in your way and can give visitors/commuters a visual idea of what they should be taking instead of their current mode of transportation

Some grocery stores in Toronto, ON, Canada used to charge 5 cents (and you got a decent quality bag reusable for garbage etc) then the City decided to make all stores charge 5 cents for plastic bags as a method of BYOBag and it has worked.  An idea that was long overdue.