The shop with its premium currency is using several dark patterns. I think it is not illegal per se (at least most of the EU), but it is a shady business practice.
It has NO use for the customer and acts only as psychological manipulation.
Vermintide 2 was great in that regard:
- sales, not only timed skins
- no paid premium currency, everything had real money prices (or used Schilling)
- because it used real money, no money was “left” after a purchase, so one did not need to get more to use it all up (unlike now, most packs have less or more Aquilas in it as are needed to buy a skin, so one needs several packs and/or has some Aquilas left at the end (aka spent more money as he needed to))