What is going on with basic grocery stuff lately? I go to the supermarket to buy orange squash and find something called "double concentrate" which is supposed to be twice as strong as standard squash so I only use half of it. It's twice the price of normal squash. Where has this stuff come from? Why was it not available years ago on the shelf? It can hardly be something that's just been invented.
Kitchen towels are similarly anachronistic. Why are they 2-ply and 3-ply at a premium price whereas years ago it was single ply or nothing. The same seems to apply to toilet paper.
Vinegar is continually being reduced in acidity.
Bakery bread in some in-store bakeries (notablly Asda)is positively pale in colour compared to what it was a few years ago.
Jacob's Cream Crackers look positively anaemic nowadays. I realise that baking is costly but these manufacturers are getting away with murder!
The 2 litre bottle is not larger in height - it's the diameter that is increased. Like you, I am no expert in plastics but it strikes me that there is scope for a compromise here during manufacturer of the container by careful design. A double size container is not necessarily twice the cost of a single size.
Whether it's height or circumference, the dimensions are different and if the price of the plastic is not that much greater, the price of the contents is a greater percentage of the cost price so it would be that which is the important factor.
I need at least 6 blades on my razor these days. I used to get away with one, but now I need one to shave me close, then another to shave me closer still, and another to shave me close still, another to shave me close still, another to shave me closer still, another to shave me close still.
There's still a tiny bit of stubble left though, so 7 might be better.