It's ironic that you accuse him of having personal interest when people have accused you of the same thing. People are allowed to have opinions without having a personal stake in any of the businesses.
Regarding the assertion that Bingo never loses money on sale items, this is patently false, and I've personally confirmed it. One recent example is their Lakewood sale on POTF ice cream. Absolute loss leader, and it actually made the manufacturer upset, because it caused them problems all over the country.
Regarding the stale crackers, it happens in every store, and it's happened at Bingo more than once. They do buy in quantity, and they always run the risk of items not moving as quickly as they projected, leaving them with old product. They have also been known to take short dated products in order to get crazy deals. Again, not exclusive to Bingo, but don't make them out to be the saints that they aren't.
Regarding the pricing, as you've noted, they employ a model which is very popular now called concessions. This means they operate the grocery store, and 3rd party vendors run different departments (ex Birdsboro for poultry, Mechy's for deli, etc.). With that model, they control the prices of the grocery, which is why you'll usually find uniform pricing on those items (except for locally targeted sales). They also have pricing guidelines for their 3rd party vendors, but the actual price is set by the by the vendor. A possible explanation for the current chicken pricing in 5T is that they are trying to break into a new market. The pricing helps them make a splash, as well as build up the volume so that they can determine where their pricing needs to be long term. If the volume makes the prices sustainable, they may not raise them, but there are no guarantees there.