Quote from Phoebe in The One After Vegas
Monica: What are you guys doing here?
Joey: Ross and Rachel left us a message saying they were getting married. Isn't that why you guys are here?
Monica: Why else would we be here?
Joey: Well, what happened? Did we miss it?
Chandler: We actually missed it.
Phoebe: Maybe you wouldn't have if you could run in the chapel!