Well there are other alternatives, no-one is telling you or forcing you buy in-game money with real life money......the issue is the other methods suck and are very time consuming, but there are other methods other than buying in-game money, so ultimately you can't complain there's an option for those that want it right away and the option for those that don't mind "working" to get it
On a side note I wouldn't mind "working" for it if there were more fun ways such as idk more multiplayer ways of being able to make money, just so it's not you by yourself there earning cash all the time
On a side note I wouldn't mind "working" for it if there were more fun ways such as idk more multiplayer ways of being able to make money, just so it's not you by yourself there earning cash all the time