I prefer to frame it more like this: "People in your age range drive less or cannot legally do so and as such have few other options for transit, so we'll give you a discount. Also, the negative externalities of rail travel are far lower than other modes of transit so we should encourage as many people as possible to use it. When a frequent young user of rail transit grows out of the lower price bracket, they will likely continue to use the service to help keep it affordable for all."
alt Hacker News
I prefer to frame it more like this: "People in your age range drive less or cannot legally do so and as such have few other options for transit, so we'll give you a discount. Also, the negative externalities of rail travel are far lower than other modes of transit so we should encourage as many people as possible to use it. When a frequent young user of rail transit grows out of the lower price bracket, they will likely continue to use the service to help keep it affordable for all."