Dis-Chem advertising wrong prices

I visited Dis-Chem at Greenstone to purchase an item. When I got to the till the item was charged under the normal price and not the promotional price as indicated on the website. When I enquired the manager said that there are many items which the prices online and in store differ. Nowhere online did it say the pricing displayed is for online purchases only. Instead, there's a section below which says "find in store". This is false advertising and a waste of out time and petrol driving to the stores to purchase items. We choose stores due to the pricing and when you get there the prices are different.