> Chicago has some all-night rail service, but it's mostly just buses, for instance. Anyone that can tends to avoid (e.g. prefers to live off the red/blue line

> Chicago has some all-night rail service, but it's mostly just buses, for instance. Anyone that can tends to avoid (e.g. prefers to live off the red/blue line) the lines that do not operate 24x7. Not providing universal service means you lose peak time ridership as well, as witnessed by ridership numbers on those lines.