On American formalism

One thing we are noticing here in the States is how formal people are.

Sir and Ma'am are very very common. Even when someone who knows you is talking to you, they might call you sir or ma'am, depending on your gender.

Odd.

Very odd.

Australians don't use sir and ma'am/madam much at all. When these terms are used by Australians, it means someone is trying to sell something to you. Therefore we don't trust people who say sir and ma'am to us. The person is being overly obsequious in our understanding. Or they are being sarcastic.

Of course if someone served in the military it does modify our perceptions some, but even then, if you know our name, you are expected to call us by it, not sir or madam.