Doc browns bottles sells this pitcher you can mix an entire days worth of formula at a time. Using that you can pour 5 ounces at a time into bottles and waste less. You could also make up larger bottles and then split the formula amongst smaller bottles to waste less. It's recommended not to do half scoops usually but so many people do.
We use this. I love this pitcher. It mixes the formula really well. We were out at the mall and I had to mix formulain the bottle. It clumped up in the nipple, got insanely foamy, it was disgusting. I will swear by this pitcher forever, I love it.