So why would an team refuse too surrender?

So I've just got out of an loss with Ashe: I was underleveled compared to the enemy, I kept dying, I felt like giving up, the match was going on for too long. So I did the rational thing and voted for an surrender...more than once. Guess what the results were....3v2. EVERY. SINGLE. TIME. Look, I know it's "fun" to fight to the bitter end, but why?

I am an Acoylyte in the Sunken-Costs Order of Thought and our logic dictates that if something is unworthy of the investment, then it should be abandoned and forgotten.

Now the average person's train of thought would be something like this... http://douglasecastleblog.com/wp-content/uploads/2013/10/Sunk-Costs-Emotional-Attachments-Which-Cause-Us-To-Continue-To-Invest-Despite-The-Apparent-And-Growing-Losses..jpg

So right now I'm curious as to why would you want to fight in an losing battle when you could earn more IP for the first win of the day?