System says it is in stock, but it is not

I went online to check the stock of a product I needed. It said in stock at Silver Lakes Makro so I drove the 11km to Makro only to be told they are out of stock. I ask for the manager and log on to the Makro web site while in the store and still says in stock. I show the manager who checks on his computer and the system tells him there is lots in stock. He searches the shelves and mumbles something about wrong barcodes and agrees they are out of stock. If they knew about some wrong barcodes why did they not fix the stock data? So I waste R44 on fuel because of a Makro problem/