Nothing stops someone from doing that today by dropping gold bars from their ship and having players collect, sell, and return until the transaction is complete. Simply transferring credits would offer a quality of life for players who don't have the time to invest in this game. As often said, some gamers have more time than money, some have more money than time. Catering to both sides is a strong business strategy.Gold Farming opens the door to out of game trading of in game resources using real world money.
As for the act of wanting credit transfers vs those that don't, the simple answer is human psychology. Our species has a long and rather violent history of people with difference of opinions. It's best not to try and understand or explain why, just simply accept it and move on. "Smile and nod" as I tell people.
The real question is what does FDev want to prioritize? They have a limited budget and team size. Based on their history, they've flip flopped on ideas, never really executing on them to their full potential. A player driven economy doesn't seem to be on their radar and so there's not much reason to invest development to support player credit/premium currency and commodity transfers until they build a proper economy to support that model. Personally I think it would be a wise business strategy for FDev as it will build a stronger player base with increased player retention as players will now have a real, tangible impact in the galaxy. More active players, more engagement, more steady revenue. But that's just my 2½ pence.