"All I wanted to do was eat my breakfast in relative peace."
Certainly the bakery would wrap your breakfast for take-out!
Using your rights to step on the rights of others - seems like you were the rude one.
I do think that people are more polite if they know that the people they, without sidearms present, are offending, are being offended.
I think that the sight of a sidearm on someone's hip reminds them not to be asses.