This is the sort of thing I wish that schools taught in "home economics" -- e.g. that sales are often not real bargains, to make buying decisions on the basis of value not strictly "discounts" that are available, the true cost of credit card debt, etc. Instead we learned how to make peanut butter cookies and sew on buttons.

You're absolutely right. This is the result of effective marketing. We're told "buy on these days, you'll get the best value" while the exact opposite is true, yet very few seem to take the time to work it out.

However I do still believe some level on consumer protection is necessary. I do not think we ought to let the less-savvy be taken advantage simply because someone is smarter than them. Where to draw that line? That's always in flux.

Very much agreed. And this was very much the case on specific days. Prices do fluctuate, but there were definitely products that were continuously inflated over the course of multiple days.