I think the broader point that several people have made -- that we make comments on other people's lives and bodies and they hurt, sting, or anger -- is excellent. And it is part of a general breakdown in etiquette, in what is acceptable.
When I was growing up, I was taught that there was no excuse, ever, for making a personal remark or query -- never to a stranger or acquaintance. And to be very, very careful with even a friend. These are rules made up when married people addressed themselves, in private, as Mr. and Mrs., and obviously society has changed -- and in many, if not most, ways for the better.
In America, at least, we blame this on the TV talk shows. It's encouraged generations of people to bare their souls in public and, therefore, since that's what people see as they grow up, of course they'll go up to a total stranger and say, "You'll blow away in the wind" or "You're too fat to fit in anything in this department." (I don't dwell on these things, but I do remember once, in my relatively thin days -- 60 pounds ago -- going to buy a suit for my mother, who's a size 8. The saleswoman, in the nastiest tone imaginable, said, "And what size would Mama be?" obviously assuming that I was looking for (gasp, choke) something in a Size Huge.
The problem with impoliteness is that polite people have no defense for it, because the only options seem to be to shoot back a retort or to leave what has become a battleground.
This is another thing that can be changed -- very very slowly -- by personal example. One person in an office who refuses to join in the gossip pool can shut it down. I saw this recently with someone who had been the subject of very vicious gossip for more than 15 years. Someone would tell a story "I heard that X" and usually others in the group would pick up on it and share other stories. One day, one of his friends said, "Does that really sound like something he would do?" "No, it doesn't," said the first teller of tales. One person really can make a difference.