Dean listened intently to the Powers as they spoke the damning words. No one could kill Ruby. No one could send her back to hell, on the offchance that she could grow stronger there and fulfill the destiny she saw for herself. Well Dean intended to make her life a living hell until she saw reason.
When they turned their attentions to Sam, Dean nearly acted on instinct. However, Claire nudged him with her side, providing just enough time for the partner to continue speaking. They were giving Sammy a second chance too. Not a shocker, when you considered how much the Winchesters did in and around LA and how much they loved Sam.
He took one last look at his brother all but hiding behind his girlfriend, then nodded back at his own girlfriend and son.He wanted them to go find a way home, to get out while the forces were relatively distracted and generous, but he resisted. The last thing he wanted to do was draw attention to them...the last thing he wanted was to have the Powers give up on the Winchesters entirely.
"Why don't we just save us all some time and shoot her now? We have a gun that will do just that," Dean promised softly, trying to get what he wanted one last time. "That way we'd save the resources by doing it once instead of paying more for less later when everything else was goimg crazy