And it gets even more complicated. Some Americans think it's polite to call a man sir or call a woman ma'am or miss, but others think it's ageist, obsequious, or manipulative.
Likewise, some Americans think it's polite to call women hon or honey, but others think it's sexist.
So in the same vein, words like buddy can be meant to be friendly but won't always be taken well. Others words used the same way in the US when talking to men include sport, man, chief, dude, bro, and guy. Other words for women include sugar, darling, and sweetie.
If you travel here, don't be offended if you hear them, but don't use them yourself. It's better just to skip those friendly tags when you talk with strangers.