.....Seriously? This is what is considered offensive these days? I mean, really, never in my wildest dreams would I have ever thought being told you're tall is somehow insulting. I guess I have been offended since I was a child, since I was always told by people that I was short. One look at my parents though, and it wasn't THAT strange that I'd be 5'1" when dad was about 5'7" and mom was 5'3". I even played basketball in elementary school, and was one of the best on the team, to the shock of my coach. On the other hand, now that I am older, the fact I am short probably helps in making people think I am younger than I am, so I welcome it, even though some men have said I am too short for their taste, which is fine, because unconsciously, I am attracted to the shorter guys anyway because it makes it easier for me to wrap my arms around their neck without having to stand on a chair or a step :)
Now my kid is constantly told she is little (she prefers the term "petite") and has been told she looks like she is 6 years old, despite being 10. It seems to bother other people more than it bothers me. Doctors were asking for her bone growth chart until I told them I was slow in growing myself, I am 5'1" and her father is 5'5", and then they laid off. Mom is always telling me to tell her to jump so it will make her taller (?). Kiddo will be happy if she is my height she says, and she's less than a foot shorter than me, so it looks like she may just get her wish to be mama's height. It used to bother me that I was short because people made it out to be some huge flaw, but unless I am sitting in a movie theater and have a tall person in front of me (in which case I change seats and the short guy will suggest doing so before I even open my mouth because he can relate), it doesn't bother me anymore. Even when my mom and sister berate me for wearing flats at times and doing nothing to appear taller, I just don't care to be uncomfortable and wobbly.
My mom is always telling other kids that they are tall and look older than they are. The kids giggle and enjoy hearing that, so I am not sure why you think that is an insult, when it is in fact a compliment. Kids LOVE being told they look like a sophisticated teen, rather than being called a baby (some classmates called my daughter that), or a midget (I've been called that). I guess to me, pointing out someone's height is no different than saying "wow, your eyelashes are so long and dark" or "your eyes are so blue". Unless it is meant in an insulting way "wow, you look like Godzilla or the Green Giant", or "hey, little dwarf, go back to your mushroom house", I would not take being called tall or petite as an insult. It is just an observation, no different than being called full-figured versus slim or long-limbed. Facts are facts.
We all come in different shapes, colors, and sizes? And? So what? Accept the compliment, say "thank you, it sure makes shopping for jeans easier, since she doesn't need to have them hemmed" or "thank you, we're all on the tall side in my family, so it was bound to happen" and move on. Focus on more trivial things, like your child's confidence, education, ability to socialize, and growing her intelligence, than whether or not she is perceived as tall or what others think of her or you.