They have been doing this to products for years. Any time the bottom of a bottle has a deep lump inside the bottle so it looks like more product than it is, any time the amount of product is a really odd number, I automatically assume they've cut back from what it used to be, even if I was not familiar with the product before. They assume people are shopping distracted and won't notice.
You're right.
We often see products on sale with some sort of indication that they will no longer be sold.....only to find out they are now in new packaging with less product. Yup, there's no inflation. Believe what the central bankers tell you!