This was taken from the design archives and although refering to economy buying credits would have the same effect over time. A playing buying credits devalues in game currency.
It does, but that can be countered by implementing more and more gold sinks, often attached to common everyday activities, such as traveling, mining or trading with other players. Guild Wars 2, for example, allows (in)direct cash to ingame gold conversion. Although inflation exists, they keep it under control, by, among other things, controlling the
exchange rate.
The problem for me is that cash shop games, both buy-to-play and free-to-play, tend to have microtransactions as their core feature, not as a tributary convenience. It means that most design decisions are analyzed from cash shop perspective for possible profit. Features are added, modified or cut depending on their cash shop potential. This practice extends down to even the most minute rules, such as making some classes of items (un)tradable, time-gating player actions, introducing additional currencies or tokens, etc.
Of course, the producers want to make a profit. However. The traditional approach (buy-to-play or sub-to-play, without cash shops) had them put in all their efforts into making a game that people will love to play as it is, and therefore gladly pay the asking price. On the other hand, the new model makes them focus solely on first selling the base game (in the case of buy-to-plays), and then on leeching money, usually in the most nontransparent way possible, by constantly annoying people into cash shop for that elusive burst of joy and satisfaction, that should have been game's fundamental feature to start with.
Can a game have cash shop and still be fun to play? I would mention Path of Exile as a commendable example, because even though it is a free-to-play game, and it runs on their servers, they've allowed people to actually have loads of fun without pushing them into spending cash. And no, real money won't buy you any currency, item or booster in that game. All you can pay for are character slots (many to start with), stash tabs (pretty decent by default), decorative pets, some fancy textures and particle effects. If E: D goes that way, I would definitely purchase it. And if its cash shop turns out to be transparent, up-front and
strictly cosmetic, instead of the commonly encountered toxic messes of shady advertising and Trotters Independent Traders business practices, I would actually buy me some cool particle effects and bobbleheads
