[KyleGoetz]

It's not formal. It's more accurately labeled "polite."

THink about it this way.

Formal in English is like "I heretofore bequeath you blah blah" or "You honor me with your presence blah blah."

Polite, on the other hand, is the avoidance of "yo foo, how you doin' aight" or "i ain't gunno go over there, so you best git, son."