I have never understood this - PS4 store is the same. Other than for profiteering, why does a digital download cost as much as a physical copy? There is hardly ever a game which you will want to replay and you can not gift or sell a used digital download.
Perhaps it's because making digital games much cheaper would ruin loads of businesses? Or am I being silly for believing that massive corporations have feelings?... I'm sure these shops are beneficial to their business plan, and undercutting them would render those businesses unfeasible.
With digital games, there are almost no costs involved. No physical blu-rays, no machines to press them, no cases, no shipping, no booklets, no insurance, etc.. And yes, the customer is limited in the fact that he/she has to download the game, cannot trade/sell it, cannot give it away, has to re-download it if deleted, has to download it multiple times (each console), etc. All this is important when each download is 50gb.
Here's the thing... I only buy my PS4 games from the PS Store. Why? Look up game sharing.. If you have a mate that has a PS4, you can buy one copy of a game, and both of you can use it. Same story with the PS3. So you're effectively getting the game for half price, assuming you split it.