False advertising

Hi, I bought the pampers special at Forest Hill mall and I was charged R420. When I enquired I was told that it's 209 for each packet and not a set. Today a friend went to buy in Sandton and she got a set for 209. I'm coming from Forest hill and they refused to give me at that price, I ended up taking my money back. How come se stores can sell it 209 and some charges more? I drove 14km to go to the store, I wasted my money and time.