It's more common in primary school to early high school for that to happen. People are insecure and feel the need to better themselves by bullying. Once you get to year 10 and over, that fades as people mature
How Many Kids Get Bullied Because Of The Clothes They Wear?
Wow thats a great Qs id say millions worldwide but remember its not what you wear its who you are as a person that counts to get on in life.