a) there is space in the middle of the car: move in and stop blocking the doors.
b) if this were new york and you wore your backpack in a crowded train or bus, someone would undoubtedly tap you on the shoulder and say with a smile “if your fucking bag bumps me one more time, i will rip it off you” — true story: take your bag off and hold it to make more room.
c) the worst place to take your time meandering, checking your phone or talking to a group of friends is anywhere in the vicinity of the turnstyles or exits: get out of the way or at least get out of my way.
Will Dao 