by AlenaI don't think I'm being fake when I'm polite, especially since when I don't know the person. I don't like being rude unless we've truly established a sort of friendship.
"Good morning, Sir/ma'am(person you aren't really familiar with)" sounds better than "mornin' fuckface."
by TurncoatSarcasm is likely to be taken too seriously as part of a first impression while politeness can help for conversations where the two aren't really talking to each other in the first place.
You still fit within what I typed, and yes, it's still extremely fake. "Mornin' fuckface" has loads more charm with the right confidence and delivery, but above all it is still far more honest. Even a "Hey there" is more believable than "Hello there sir or madam", and if the latter it better be followed promptly by something like "May I take your order?" or I will not be a fan.