If you've always been sold a dozen eggs in a package that can hold twelve eggs, but suddenly the same package is relabelled and used to sell you only ten eggs, who in the world looks at that situation and says "as a rational market participant, I can't be mad because the package has indeed been updated to say 'ten eggs' and I just failed to take notice (yolk's on me)."

People like to be dealt with fairly. When they occasionally notice things that make them realize there are rooms full of people whose entire job is to trick them, they don't like it. Where's the mystery?

So much of modern life boils down to this.