Another Tesco conundrum

Another little "I wonder why" from the shelves of Tesco, Penicuik, - sitting side by side on the shelf, same product, so how come one costs £2.66 and the other £3.20p per 100 gms - just does not seem to be any logic to this other than to diddle the customer.

There also appears to be a cartelling going on, especially when Sainsburys, Asda and Tesco are all offering to pay the difference if you spot it !!!