Aye, they do. Most bullies back off at least when you show them that you're not willing to be messed with.
You know what I never quite got as a kid? People who went round saying that "bullies are cowards". They were deliberately picking on people and beating them up 'cos they're bigger and stronger! When you're a kid, that doesn't make you a coward, that makes you terrifying.
As an adult, sure I see it differently, but as a kid? Could never understand it. Even when I stood a foot taller than everyone in my class.
When I was a kid, apart from a few months when I was 15, I never did any MA.
As an adult? Yeah, a few of the local hard nuts on the estate I live (a couple of gypsies, dude who boasts about being hard core because he used to practice Ving Tzun, another dude who was thinking of taking up kickboxing) have watched me train a few times with the makiwara/pads/couple of other bits. Even joined in a couple of times. I'll spare you the details, but it has been...pretty entertaining, even with injuries that seriously hamper my mobility and training
Strangely though, they've gone from having a lot of respect for me and bragging they wanted to take up kickboxing with me to doing whatever they can to avoid me while giving me dirty looks. I don't know what's changed but frankly, I like it this way.