Dis-chem misleading adverti*****t of free gifts .

So tired of dis-chem offering free item when you buy something, and at the check point, they never have the free gits in stock, happens to me time and time again. Im wondering if its only a **** to make you buy certain items , and also more of that item, as its usally buy 2 of these and receive a free..... Im not going to get caught again.