It's very unkind and is only being done to make you feel bad about yourself.
I spent a childhood being cold and wet. I spent my late teens being cold and wet. I spent my early twenties being cold and wet. I spent my late twenties being cold and wet.
This was because I didn't have a decent coat after I was about 5. I saved up from my Saturday job and bought a dark green duffle coat, only to have the piss ripped out of me for dressing like Paddington Bear. I didn't have a coat again until I was about 27. It looked so disgusting according to my then partner's ex girlfriend that he gave it away, leaving me without a coat. Once I'd got out of that relationship, I couldn't afford a coat.
I saved and saved until I could buy myself a beautiful, pure wool, tailored coat so that I would be warm and smart and have something that would last me for years. It took a good five years as every time I nearly had enough, something would come up that was more important including where I had been unwell and lost a lot of hair previously due to medication. - but eventually, I had the coat, my hair was looking and feeling better and I looked forward to the first properly chilly day.
According to the then boyfriend in between doubling up with laughter, I looked just like Uncle Fester. He kept calling me Fester all day in public, all evening, told his mother, his sister, her boyfriends, their kids and every time until I finally dumped him that it looked a bit cold or wet 'You wearing your coat, Fester?'.
Once he'd been kicked out, I thought I'd be able to wear it at last. Nope. All I could hear in my head was the hours and hours and hours of 'FESTER! Come on, Uncle! Take that wig off Uncle! Where's Morticia?' and the theme tune, combined with the idea that his first thought was that I should be told that I looked like a bald monster.
I still don't feel like I look right in any coat.
It's designed to knock you down a peg or two, to make you feel stupid and inadequate and ashamed of thinking you looked good or was worth something.
So can you imagine how anxious I was when a new man invited me to a special occasion I'd have to dress up for? I was convinced he'd laugh at me and was nearly in tears by the time I opened the door, so as soon as he looked at me and he started to smile, I burst into tears. Difference is that the man at my door was my now DP. He had started to smile because I looked beautiful and whilst he knew he really, really liked me, he absolutely loved the outfit and hadn't expected it.
It's bullying, plain and simple. And people who laugh at bullies are indistinguishable from bullies themselves.