Open the new one. It'll fatten up when it sucks in some air.
That would be the comparison to make. I want to see how they shaved 3oz. off when the bottles look nearly identical. Betting it's mostly in the top.
I'm not one to be cynical and see evil shit everywhere I look. Some decisions that look bad on the surface were made for reasons we're not privy to.
THIS shit however... Someone said, "We're going to shave 10.7% off to raise profit. But we gotta design the smaller bottle so no one will notice. Oh, and we have to retool the manufacturing lines."
And then someone make a spreadsheet calculating the retooling cost and when it's expected to be recovered from the extra profit.
Their point was that they didn't redesign the package to make it slimmer because that would have cost way more to do than just filling the same bottle with less liquid.
I actually work in a food packaging place and you'd be surprised at how easy and simple it is to make these adjustments. That said, at least it's not as dumb of an argument to make.
These bottles are blow molded to loose tolerances at huge volume, not injection molded or milled to tight tolerances at low volume. The cost of changing up the manufacturing lines for this is not much