Aspie is a term most of us use to avoid spelling out "Asperger's Syndrome" each time we write. For those who don't type 120 wpm, that's a pretty big word.
If you show stereotypical signs of Asperger's and your friends or family (or therapists, etc.) use the term, it's a diagnosis. Just like someone who is "legally blind," can often see "a little."
There are some traits shared by many people with the same issues, which are symptoms or keystones of the diagnosis. It's not a "label," unless you choose to make it one by using it (or being offended by it).
Almost every Aspies is different -- even in highly professional, well-paying positions. Some are more functional than others, and if someone wishes to share a diagnosis with someone else, that's their prerogative.
However, when you are socializing with others on the ASD spectrum, they often use it (Aspie) because it's a separate "area" of the spectrum.
If you don't like the word, you don't have to use it. BUT, to many of us (even if it's just to speed up typing speed), it helps us identify others who need advice or support (and doesn't slow down the typing speed).