Team based game, but no team based score?

It was brought up in conversation recently, that points earned do not reflect the team, even though the game is clearly team based.
Dragon Age Inquisition Multiplayer has this down to a Tee, so why does this not work on or for Horde, or now, Escape.
As an Engineer i see a lot of people leave the game, sometimes because my Sentries are owning the game, of course this is not my fault, i build to defend, not to offend.
I see the negative side of it, because we joke about it on Dragon Age Inquisition Multiplayer, someone just joined a game you 99% just completed on your own, they get the same experience as you just earned.
It is however, a better option than people leaving, if you are owning the game. it does not mean you can sit back and enjoy the show, you play the game to play it.
I was in a game the other day, just over 30 of the 50 waves completed one person hid in a corner and was gone, earned a hefty bonus while everyone worked their ■■■■ off. Yes, there should be a kick button, for people like this, but only people like this. I have seen the kick button abused, as i have been booted from a game, because i was better than everyone else (not Gears).

Anyone else think this is, or could be a good idea.