How are they going to make up the difference in volume when they just lost one of their biggest retail contracts? It's hard to sell more of something, when fewer of your product are on the shelves, and more of the competitors are in their place.
Every store that sells automotive (and marine) batteries carries a certain brand. Many of those brands are made by the same companies. More and more of those private labels are being made by Johnson Controls, and not Exide. Losing Wal-Mart to JC is a HUGE blow to Exide, and unless they can somehow get one or more of the big auto parts store chains to switch to them they are going to have to cut back somewhere.