What do the payment options change? Every Gold Point spent for the subscription can't be spend instead to buy games cheaper.
The German word "Milchmädchenrechnung" comes to mind...
Actually gold points are worth less than the amount of money they can be used for. Because they can only be used on the e-shop. Say you have a good paying job and you get some games and gain gold points. Then something happens: you lose your job, unexpected bills or something like that. You have to save money, but you can still use your gold points. You have to think if you get a game or online for that, but it certainly feels like less of a blow to your pocket. Because basically paying with gold points means paying with money you already spent in the past.
Die Milchmädchenrechnung does it become when you include the future. If you pay with actual money, you get more gold points you could spend in the future. Although, actually I don't know if you get awarded gold points if you buy the online.