"Each death (in a row) of a champion reduces its value, by 8.5% for the first death and 20% for every death afterwards, to a minimum of 50 gold."
"Every kill (in a row) by a champion increases their value (the reward gained for killing that champion) by 16.5%, up to a maximum of 500 gold."
so, you have a little period in the beginning of the game where the enemy team has an advantage picking up kills on the feeder.
but if you play it smart, and they dont... all your feeder does is increase their bounties while they wasted time missing farm that would have paid them more.