Look, I understand that not everyone can afford a car, and that publc transit is a necessary evil. All I ask is that people sit in one seat, there luggage has not paid a fare, so therfore it is not intitled to its on seat. If you are getting off in a few stops, be respectful of those that have to travel a great distance, and give up your seat.
Standing can be an issue if you haven't showered or have been sweating all day...be kind, keep your arms down.