Every MMO in existence has external markets for RMT. There are stories of players in elite WoW guilds making 5-6 figures for helping noobs clear content.
Some people don’t mind spending $2000 to build an endgame character that’s only worth $1000 by the time they’re done with it.
We don’t call automotive hobbyists “marks” if they pay a mechanic to tune their car and devalue its resale price. Professionals/careerists exist in every hobby industry.