This happens all the time during commute hours, especially at the busier stations like Shibuya, Shinjuku or Tokyo stations. Often the guys have big square plywood boards that they use to push people with into the car. It is amazing to see and feel. I have been in there getting squashed. Think about when it is summer and the heat and humidity are out of this world. Mildew smells and sweaty faces everywhere. And just try considering what it is like to have to get off the train! Sumimasen!!