I think the reason why most shoppers aren't realizing this (at least until just recently, when it's been in the news a lot) is because they are too busy to take their time shopping like we do. Those of us who are frugal are very aware of what we are getting for our money. But most people are in a rush all the time and just throw the quick convenience, preprepared foods in the buggy and rush to get to the ckeck out line.
That's why I started shopping less often and just spending more time there when I do. I used to stop by Walmart constantly after work and pick up things here and there. A couple of years ago I started making a big shopping trip every couple of weeks (only picking up essentials in between at the local store) so that I can take the time to plan out my list, find whatever coupons I want to use and take my time when I'm in the store. I also find better deals this way.
God bless,
Julie