I totally get your reasoning. I do the same with regular milk. As for buttermilk, I recently asked the same question your brother did on Reddit just this year. How do you know when it's bad when it already smells bad when you get it. The consensus was that it's not bad until it's bad. And don't go by the expiration date. I was told to shake it up before use, and if it comes out lumpy, it's bad. One person even said that they have been known to drink a glass of Buttermilk that has supposedly 6 to 8 months old. I can't even drink it when it's fresh but I do like it as a flavor in some of the things that I make.

About pancakes, do you ever fold meringue into yours? My mom used to do that. They were delicious. Every time I try to do it, I overfold and lose all of the properties of the meringue