Yeah, you've just touched on another point that I didn't make (I thought my post above was long enough).
There's definitely parts of "real street" photography that I'm not comfortable with. In most cases I try to think "would I like someone else to take a photo of me doing this?" and the answer is generally no (part of the reason I have a camera is to make sure i'm always on the viewfinder end of it). But then I have to weigh it up against 'everyone else is doing it' and 'even if there's not photographers around, i'm on CCTV 24/7 anyway'.
There's a guy over at CR, he takes his 1D mkIV and 400/2.8 on a tripod, down to the local drinking strip at 2am, and photographs drunks coming out of pubs and occasional street fights. Safety-concerns aside (I wouldn't be lugging $10k worth of gear to a place full of violent drunks), that kind of photography doesn't sit well with me. Yes, shots like that can be useful evidence in criminal cases if anything goes wrong (but that's what cctv is for). But what about the guys there? I'm sure they don't want their bosses seeing them like that. What if they've gone drinking straight after work, wearing a shirt with a company logo, have a shot taken of them near a fight (even if they're not involved), boss sees the photo and decides it's a bad image for the company and they get fired? (obvious answer would be to get changed after work, or that maybe just being in that place in that state is reason enough, the photo is just the evidence). Living your life like someone's always pointing a camera at you is not a bad way to live, i suppose.
And then there's another counter-argument to that. Lately I've had a heap of friends get married, with the inevitable bucks' shows that end up at titty bars. I don't mind being seen going into one, but the thing is, I didn't. I don't have any major moral objection, but normally by that time of night i'm about to fall asleep anyway, and they're expensive to get into. But I have been lining up with the people who were going into them, I went into the entrance foyer to say goodbye to the buck and all the rest going in, before I left to grab a taxi home. Would I have minded if someone had taken a shot of me then, lining up or leaving? Strangely enough, no, had i gone in and enjoyed the show. But had someone taken a shot of me, accused me of going in when I hadn't, that I would have a problem with (maybe I'm just weird).

I don't know, it's all mixed shades of grey area, so that's why I shy away from that sort of 'candid street' photography. If you can't see the faces or anything else that makes the subject readily identifiable, then it's fair game, I suppose.