Escalator Etiquette

There are unspoken etiquette rules that everyone knows in life - walk on the right in hallways and malls. Don't talk loud enough in public places for everyone to hear your conversation. Don't stare at people on a elevator. Don't fart on a crowded CTrain (my husband's suggestion!)
And courtesy when you ride up an escalator dictates that you should leave a step between you and the person you don't know in front of you. Most escalators do not have wide enough steps so that a humans personal space is not invaded by the step behind them.
I am commenting on this because last night I went to the movies with my sister (we saw "Music & Lyrics with Drew Barrymore and Hugh Grant, really good chick flick, BTW!) and you take an escalator to get up it. The people in front of me were together 3 on 2 steps, which is good and I left the courtesy step between us. All of a sudden I felt someones presence behind me and could almost literally feel his breath down the back of my neck. I partially turned my head to the side to see a guy's head right at the same level as mine... right there! It scared me a little and I had nowhere to go to get away from him. I was not going to be just as awful and invade the people's space in front of me. Luckily it took less than a minute to finish the ride and I could get off.
Just thought I'd share, its been on my mind since then and though I ranted to my sister, I thought the rest of cyberspace should know too.
Storal of the morey is... sorry, Moral of the story is...
Please leave the stair between yourself and the person in front of you next time you are on an escalator, you never know when someone might need their personal space.