It's rude to push people when unprovoked.
Amy was late for work and there was a long line in front of her waiting to get on the train including an old handicapped woman.
Amy wants to get to work on time.
Amy notices a shorter line at another train door and runs there to catch the train.
Amy pushes the old woman in front of her out of the way so that she can get the last spot on the train.
The old woman is able to get on the train and get to her doctor's appointment on time.
The old woman misses her doctor's appointment when the train takes off without her.