Big "SALE!" signs and prices ending in 9 aren't benign: they're malevolent attempts at psychological manipulation, and they degrade consumer trust the minute customers recognize them as such. While it's likely impossible to fully counter the bias, I've started clutching my purse strings more tightly since those big glowing signs became less of a declaration of value, and more of a warning that "We don't have your best interests at heart"
These techniques work, but only because people view this manipulation as acceptable and commonplace. It would do wonders for consumer confidence (and therefore sales) if stores could give a credible and transparent promise that they make every attempt to inform consumers about the value of their products. Shoppers like myself (busy, uninformed about most categories of things they buy, and unconfident that they can navigate the "DEALS" landscape and come out ahead) would not only shop there: they'd pay a premium to do so.