I never rage quit because of archers.
When I am presented with a challenge like that I grab a siege shield and hunker down...or get my teamies to bum-rush the archers.
Typing in ALL CAPS in team chat repeatedly can sometimes get your team to work together. I've also written a guide on how to avoid getting killed by archers! It's in the beginners help/guides section.
Sometimes though, if I log on to NA seige and I see KUTT makes up 80% of the enemy team and is on defense...I will log on to a different server to play.
Those guys got it together sometimes!