As much as you have a valid point about it not affecting others... the thing with this kind of micro transaction means that it will set the game on a dark path.
Apart from reputation, the game only rewards your activities with credits.
By selling credits for real money, what you are doing is effectively stripping out the only in game reward for activities, and replacing it with a "Spend money to get reward now" advert.
In fact, if you take that... you get rewards for completing missions and other activities. If you are able to straight up buy the reward without any interaction in the game, wouldn't that define the game as "pay to win"?
I mean, most people define pay to win as a way to gain an unfair advantage over other players.
But if you think outside of that... you are effectively paying to win your single player experience by buying the reward straight up.
It would turn the game into a mobile-like game. Where even the single player games offer you to just straight out buy in game credits, which you should be rewarded for completing activities.
These mobile games are defined as pay to win, even with no multiplayer, so the same would also apply to ED, if it were to ever happen.
And from my own subjective point of view, if it were to ever happen, I would simply sell my joystick, uninstall the game and never touch it again.
And I'm fairly certain, I wouldn't be the only one to never play the game again.
