I can understand where that's annoying. & I think the comments about how we are thinking of motives are dead on. lol
Sometimes, to me, it just seems like someone's social & they have to talk about something, so that's what comes out of their mouths, like at a store or something. lol Sometimes it does seem like they're trying to butter you up, which I don't respond to either.
Actually, now I get insults, too, I think because of where I live & also because of PUA culture. (That's big here.) See, the new technique is for men to put you down if they think you are pretty. This is supposed to make them stand apart from other guys & make them not look desperate. So, instead of saying they like your hair, they'll say. "Your hair's nice. Is that your natural hair color, though?" Like, they want you to be uncomfortable, instead of flattered & this is supposed to give them an edge. Or, someone might say. "I usually only date models, so I don't know what it is about you I find so attractive. We must really have a connection." The thing now is back-handed compliments. These are called "negs." So, be careful not to get sucked in thinking they're being honest. It's not like that.
Compared to those turkeys, I'd rather deal with those inclined to compliment! ;)
I started writing, though, to say, every now & then, someone is 100% sincere. My grandfather was this way. He complimented everyone, all the time, about everything. He was a jolly, happy man. He truly just loved everybody. & he really thought every woman he met was beautiful & told them so. He very often told men they were handsome. He's say, "Hi, handsome!" He saw everybody through rose-colored glasses. He'd see a woman in her eighties at the doctor's office & tell her, "Seeing you just made me remember what beautiful creatures women are." But, he meant it. He always really did. :) He wasn't skeazy or creepy, but it was like everyone looked like a movie star to him. He was always in awe of how wonderful everyone was. Because of him, and because of how special he's always been to me, when a gentleman I don't know lays it on thick, I can't help but know there is a very slim chance that he has a similar personality type to my grandpa. So, I can't be irritated, just it case it isn't actually sleazy. I'm not a mind-reader, after all. :) So, I smile & say thank you (but leave quickly). That way I'm covered either way! lol