I think that Buffy believes it's for the greater good, and therefore, all ramifications behind those actions are irrelevant. Like jumping through the portal with no guarantee of her coming back. Or making all of the potentials slayers with no plan on what the crap to do with them. Going to the vineyard and into the Hellmouth. It's the big picture that matters to Buffy. I don't agree with it, but that's what I think is happening. She's become hardened over time. Her decisions essentially boil down to "what's the best way to fight evil?" And if that best way is robbing banks for the general greater good (though she hasn't been doing that for all of s8, apparently), then it's okay to do. A far cry from AYW, and a huge disservice to not explain. And I'm just speculating, clearly :P Or talking out of my ass. Whichever works.