Twelve for the price of one

"Knopfzerbrechen" prepared the cells to me has always been because the replacement is usually associated with high costs.
In typical electric market or hardware store should the usually (regardless of type) per piece 4,99 EUR - the "house brand" then 4.49 EUR.
I have a perfect and quickly get delivered for a lower price in comfortable cushioned envelope into the house 12 button cell. This is hard for the retail outlets.