Why does dodging a ranked promos game count as a loss?

I just baaarely made it to silver 2 today. Thank Riot for the promotion forgiveness free win thing, because both of my last promo games had intentional feeders in it. And my first promo game today had one too! He said he was going to feed in champion select, but I figured might as well play y'know? Since dodging counts as a loss anyway. It went as well as you'd expect. I know it's going to be crazy these last few days of the season, especially since it seems every other player is boosted or trolling.

And I do understand this could be abused. In your promo and you don't like your teamcomp? Just dodge. But consider this; the good would outweigh the bad. There will be so many more people dodging to avoid a troll than dodging to... abuse this or whatever. And it's not a perfect Sol by any means, but until Riot implements a way to deal with these kinds of things, we sort of need a way to dodge these trolls. The queue time increase (5-20 minutes) is a good deterrent as well.

It's just so miserable to climb when trolls have access to your information. "He's in promos," they might think to themselves. "I'm already gold so idc. Time to get my feed on!" Thankfully I have trust in Riot's punishment system (as seen by so many threads here) but it doesn't fix the damage already done. So.. yea?