This seems like a mis-read of the demand that's out there. The Cubs easily could command something approaching $300 per ticket for the best ~71 tickets behind the plate (the ones not already priced there), without the club and lost suite revenue. Instead, to avoid the PR hit (I guess?) they've added a ticket category of mediocre seats at sky high prices rather than raise existing seats to market price.
The Cubs seem to have derived this idea from the Yankees and Mets, who both added similar expensive, all you can eat clubs at the suite level way down the lines in their new stadiums.
They both sat largely empty for most of the year.