Everyone in my neighborhood is used to me and waves when I go by, maybe because I always wave at them - I'm just known as "that BF runner" to most. Occasionally I'll stop and chat for a minute or two when I meet one of the regular walkers. Any runners, we'll usually just nod or give a lazy wave to each other as we pass.
Most of the positive comments have come from other (shod) runners. My favorite so far is "You're a rockstar!", although that's somewhat negative because it implies most others can't do it. I've heard "awesome" and "lookin' good!" a few times and when I get "How do you do that?", I just answer "Practice!"
Once as I was approaching the finish line in a 10K I heard a young boy exclaim to his Dad "See, his feet aren't bloody!" Another time, someone commented "What happened - did somebody steal your shoes?" and I said "Yes, and they took my lunch money, too!"
But most people pretend not to see me - like I'm a bit of a nut, maybe even psycho and no one knows what I might do next. Once someone drove by, stopped in the middle of the road, backed up, rolled down the window, and asked if he could take a picture - all this on a hill and a blind curve! - now who's the crazy one??? If they do make a comment, it's usually stating the obvious (Hey, you're barefoot!). On rare occasions, someone will ask about BFR.