Subscriptions and Cashshops

[Ranaku]

There's no justifiable reason for the cash shop to even exist in a game that you have to purchase to play and also pay a monthly subscription.

I just wonder what people think would be a better solution to the problem of inflation/higher maintenance costs and all that. The thing is that the sub fees are staying basically the same over years while maintenance costs and employee wages and all that goes obviously up, so without profit from other sources company growth would stagnate. But if not a cashshop what would be the better solution?