Let me set the scene for you: it's 8 am, I'm on my way to work via a CityRail train, and I'm not in the greatest of moods after finding that my uniform didn't dry properly and the EFTPOS on the ticket machines stopped working. After being waylaid by an old lady who couldn't read the digital displays and a horde of young school children who I'd like to smack but probably shouldn't, I've missed my train and am running late. By the time I actually manage to get on the train, I'm pretty pissed off.
Then two stops later YOU get on the train. You check out the ample seating on the other side of the carriage, but decide that the empty can on the floor in front of the seat is off-putting enough to warrant sitting on my side. Ok, fair enough. But there's enough space beside me for a Tongan football team; the train is practically empty. Why are you sitting pressed against me?!? WHY ARE YOU ALL UP IN MY GRILL?
This is my dance space. This is your dance space. I don't go into yours, you don't go into mine.
A commuter with personal boundaries.