The other day our jungle shaco, top yorick, and Vayne all fed.
Me, mid, as Ryze, and Nunu support were the only ones that weren't doing terrible, and we essentially "held the team hostage" with our refusing to surrender. At one point we were like 5 to 20, and I was personally 4/2/1.
Never surrender. Ever. If they are really stomping you THAT hard, the game will be over soon anyway by it's own accord, you may as well get all ten of you the more IP for playing a longer game. Or, maybe, you'll have a miracle comeback and get to post about it on the forums only to get it downvoted by people that are jelly of how great a game you had, so they point out stuff like how Akali had 3 gunblades.
Also: If you're not the only one on your team doing well, you should lose your rights to initiate a surrender. If you're 4/2/1 and your team is feeding, sure, /ff if you don't want to carry them and get a win that you are responsible for. If your mid is 4/2/1 and you're 0/6/1, and he doesn't want to surrender, why should you get to call a vote to decide whether or not he is capable of winning this for you? His prize for doing well is that he gets to attempt to carry you.