Interacting with other people is a part of life.

If you are traveling on a train, and the train is crowded. Your ticket does not entitle you to a seat for yourself plus a seat for your bag. It certainly does not entitle you to a seat for yourself, a seat for your bag, and a seat for your feet, as the man currently sitting across from me seems to think it does. There are people without seats sitting in the stairwell. If you are some deity and deserve such decadence, then pay for a first class ticket. To be honest, my wife does this as well to prevent anyone from sitting by her. It drives me crazy.