Hi, my name is...

"Hi. My name is..." At what age is it appropriate to start introducing yourself using both your first AND last name? Is this an age issue, or am I just weird? Wait, don't answer that. But really, when is it appropriate to use your first and last name when you are not in a professional setting? I've noticed that older adults always use both their full name regardless of where they are. I just feel strange using my full name at parties, bars, etc. It feels so formal and forced to add my last name. Why is this? Am I the only one who feels this way?

There's a scene in You've Got Mail where Meg Ryan addresses this issue. She ponders this stating something along the lines of a "whole generation of cocktail waitresses" who only use their first name. I mean, I don't think I'm Cher or Oprah or anything. I just don't always feel like throwing my last name onto my introduction. Besides, Elle has such a nice ring to it :)