Buzzfeed.com has come up with a list of problems all sarcastic people will understand.  Here's the top 5 from that list:

  1. Your sense of humor can be described as an "acquired taste."
  2. Sarcasm slips out of your mouth so often that you often forget you're doing it.
  3. You have to tell people when you're being serious, because they're so used to you making jokes.
  4. And since your default setting is sarcasm, you have a hard time turning it off when others need you to.
  5. You're never more on point than when you meet a fellow sarcastic person with whom you can trade quips.

Being sarcastic can loosen everyone up in a conversation.  Being too sarcastic too often can be a real turn off.  You'll literally wear everyone out you talk to.  Just saying is all.