First, I will call a complete stranger Sweety if the do me a favour, sort of like "thanks mate".
Second, I will refer to a complete stranger who is cute/nice as a Sweety.
Third, when I use a sarcastic tone for a person who has no common sense, sort of like calling them an idiot. But subtle.
Fourth, with this one I use Sweety instead of your name but I only do this with people I care about. See, if I don't say your name then I can remain separate to you, it's less intimate. This is my last defence to opening up completely to another person.
However if I use your name, that is the greatest compliment and show of trust.
Now, if I call you an idiot, I'm being straight. You are an idiot. Sweety is the only name that has to be taken in context with me. At least I don't use cupcake, sweet cheeks, sugar, hunny bun, baby cakes, darling, pumpkin, babe or possum.
Love ya Sweeties.