Retail stores always make a big deal about the suggested retail price because that is the best way to lure in customers. By doing that, they show how much a customer is actually saving money compared to store X, Y, and Z.
Because they want the buyer to believe that they are getting a good deal by buying it at their price. Typically the suggested retail price is much higher than the store's selling price.
It's an advertising ploy. This attracts attention and being curious you go to the store to find out their talking about. The end result you buy something.
By advertising the "suggested retail price", stores are able to show how much lower their actual prices are by comparison. This causes shoppers to feel that they are getting a bargain, and therefore buy more.
Like any other marketing tool, the price difference between the often illusory suggested retail price and the seller's "deep discount" price is only a way to catch a buyer's attention and make the buyer feel like he or she is getting "a good deal." The deeper the discount usually means the seller has a more efficient management process than competitors.
