one bad mother!

My two miler yesterday (I know, it was supposed to be three. Didn't happen.) was filled with etiquette questions. Some running related, track usage related and others more general in nature.
1. When running on a track, is it polite or impolite to let someone know you are going to pass close to them? As in saying "on your left" as we did in 2-track skiing in high school, so that you wouldn't accidentally pole someone in the face or something.
I am ambivalent about this. Part of me is like "Yes! I want to know, so that if I need to I can move over" and the other part of me feels like "The asshole is passing me! And being all smug about it! Jerk! Jerky jerk jerk!"
2. When you are walking (or doing lunges, say, with two of your least athletic girl friends) on the track, does it ever occur to you that other people, who were using the track before you got there, might become annoyed by your presence in the middle of the track, or spread completely across the track so that weaving through your group becomes a necessary navigation procedure?
I would think that someone might realize that they do not have a claim to the entire width of the track, and that really things like lunges should perhaps be done in single-file, especially around narrowing parts like corners. And walkers? At my Alma Mater The indoor track at the field house had a sign by the entrance that said "walkers inside lane, runners outside lane" and that was how it was. But this track doesn't have two lanes. Its not divided up at all. And the only sign by the door tells you how many laps it takes to equal a mile. So its a little more free-for-all anarchy in sports action than I am used to.
3. If you are a guest at a person's house, do you spread your shit all over the living room and act like it is your personal bedroom if you're staying for a week? And do you never, ever pick anything up (as in plates glasses cutlery after someone has fed you dinner, or putting away food after you've made a meal out of someone else's fridge) ?
The answer it turns out(if you are the girl from Texas who came to visit my sister this week) is no, you don't pick up anything, and yes, you do move into the living room, appropriate the couch (only comfortable piece of furniture in the room) open your luggage and spread the insides about wildly, and then decline offers to leave the room, preferring instead to sit on the couch with your laptop and IM people. Its been going on for a week now, and I am fairly outraged. I think if you're imposing upon another person to feed and house you for a week or more then it is only right that you pick up after yourself, or offer to help occasionally with... something...anything, really. Seriously.