That’s easy for you to say sat in front of a computer screen looking at 4 pics. Have you ever had someone running alongside you as you rode? A chav yelling abuse at you or a dog barking at your heels?
To the chav it’s a bit of fun and he doesn’t really intened to push you over and nick your bike.
To the owner of a dog it’s just an example of “Rover is having a bit of fun, he’s harmless”.
To the rider though it is very intimidating, you feel threatened by it and react accordingly.
Yes I have, both dogs and undesirables. I reacted by cycling on.