I tend to notice what other people are wearing, and over the years I've tried to make more of an effort to offer compliments when the situation is right. Being in the South, it has never seemed a strange or forward thing to do, like striking up a conversation with a cashier. I'm just quiet so I didn't do it so much. I like receiving compliments myself, so when I find I'm admiring something internally, I express it if I can.
As far as receiving them, I tend to get a fair amount. I've also noticed that it's almost never on a single item. People tend to notice the outfit or general effect and want to say something but sometimes don't quite know how to express it. I can recognize this because years ago, when doing living history, I got some comments from visitors admiring my outfit. And in this case, it was because the clothing was historically accurate. There were many others there with more eye-catching (and costumey) outfits, but these people responded to the rightness of the look without even knowing the history. I think I recognize something similar now. When someone likes my outfit, sometimes they'll say "Nice dress!" - even though it's a skirt and top and cardigan. Or more generally "I love the way you look!"
I'm kind of rambling since I haven't experienced the feeling of either receiving dubious comments or feeling that I've given them! Although... There was the time a young 20-year-old or so just LOVED my SAS wedge loafers that I'd bought off ebay. I was wearing a tweed skirt and dance tights that honestly can look like compression stockings and the loafers look slightly... orthopedic to my eye. I was mostly wearing them since they were comfortable and I'd gone for a walk in them earlier. I'm still not quite sure what to think of that!