I am usually pleased to encounter people I know when out and about (one thing I love about this town, same as I loved about Austin , Tx…biggest small town in the world in that respect, always running into people you know… like Facebook, only less superficial :D)
I’m not leading any secret life or anything. (“Oh shit, guess who, and, DAMMIT, here I am out w/o my mask and cape!” :p) And I can easily and politely brush off any hypothetical annoying co-workers of friends of a friend who try to impose on my current activity.
A fairly recent incident: I am a huge Tim Burton and Johnny Depp fan (lucky me, since they tend to team up so much…2 for 1:D) and I went to the premiere of Sweeney Todd here in town. As I entered the theater, a co-worker of mine called out, “Hi (my name)”.
He was there with his male date. Could have been an awkward moment for either of us (since he was not “out” at work), but instead it was a nice moment (hell, I’d known he was gay from the first time I met him and didn’t care :p).
I said, “Oh, hey, might have KNOWN I’d find you here!” (which he seemed to find extremely amusing…both due to the stereotype of gay men loving broadway musicals and us having had discussed the hotness of Johnny Depp;)).
Anyway, it was a good encounter and I would hate to live a life where I dreaded running into people I know out and about (or where they dreaded running into ME!:eek:)
Such is the spice of life and a very good thing, imo.
To add, I am also amazed at how many are indifferent or hostile to the idea of encountering people they know in some way in other situations.
Hmm. I guess I live my life so that I don’t have any/many from whatever setting (personal, work, school) whom I’d just dread encountering!
Or maybe I am just naturally more social in nature. I AM from Texas. 
I recall a flight from up here back to Tx. several yrs ago. Had to transfer a few times and it was a LONG trip. We made it to Dallas, I think it was, and were waiting in line for the next flight.
It was interesting; all this conversation kept breaking out among the strangers there in line. People you’d never seen in your life would just turn around and say, “Dang, this is taking forever! So, where are YOU coming from/going to?”
I thought, “Ahh, we are back in Texas”. 
And it was the most natural thing in the world. But it struck me instantly that it was something that would be considered incredibly odd and rude outside of that culture. (like here, were I dealt with some culture shock initially when I would say “hi” or “excuse me” to people I passed/made eye contact with on the street and they would look at me as if I were INSANE and not respond! 
)
I hope I never get to the point where I am NOT pleased to encounter those I know in any circumstance. Yes, there are a few in my life I’d not be esp. tickled pink to run into in certain settings, but I was raised (and still feel) just be nice then assert your right to privacy. What’s the big deal?
I like seeing people I know when I’m out. I’ll at least say hi and see how they’re doing. Depending on the situation and how well I know them, I might invite them to join me (say, a friend that I bump into at a restaurant).
I’m thinking that if I’m in the kind of restaurant that serves “great, unique food in a relaxed setting”, then anyone I know who happens by is not going to stand there talking to me for more than a minute or two.
Bear in mind also that in Mississippi you gotta ask about “how’s your Mama and them gettin’ along?” or you won’t have done your social duty. 
I’m in the other category - panic. I am just never sure whether to engage someones attention to nod a greeting because I am worried that they will blank me/fail to recognise me/not be happy to see me. I’m pretty insecure like that. In the past, I would have fairly deliberately tried to avoid the situation - I am less likely to do that now. But I do enjoy catching up with people - spent 10 minutes yesterday chatting in Tescos with a guy who used to do boxercise with me 6 months ago before the class stopped. I hadn’t seen him since then, but it was nice to say hello.
Si