Bullying has always gone on, whether you disipline kids or not.
Anyway, bullying is not always physical.
My daughter was a "bully" at secondry school when she and a few of her friends "picked on" another girl and always made her cry. They never touched her but it was all about teasing and so on.
The girl was so upset she had to be moved to another class. Mind you her school generally denied bullying ever went on and were very bad at handling it.
My son on the other had was bullied. He suffers from a slight disability which gave the other kids a chance to pick on him, and he would often come home with bruises, or ripped clothing. However his school dealt with it very well and always punished the other kids.
Bullying is a very complex subject and it is not always about "big lads" picking on "small lads".