A fundamental lack of logic

Daily planner at Staples 

Weekly planner at Staples

Daily planner (left) and weekly planner (right) at Staples

Normally there is some sort of relationship between the cost of a product at its selling price. As the cost of production goes up the selling price goes up. A book with lots of pages costs more to produce than a book with fewer pages.

There is a fundamental lack of logic in the pricing of the two products. The daily planner has twice as manny pages and the weekly planner. So why is the daily planner priced at almost $2.00 less than the weekly planner?