In reality the train is fueled in several ways. E.g. a tank-train comes nearby or the train is uncoupled and drives to the fueling station alone and much more variants.
And backing up into a station isn’t possible. Yet! I mean that would be much more intuitive than this, if shunting would be possible. Because it’s of course quite complex, but it would allow so much more possibilities with trains than yet.
Ok, you want to add a mechanism that is really hard to understand, because it introduces a quite big complexity (you seem to ignore it), only to … spare some stored fuel??As to why I would do something like that? Saves me half the buffer of fuel. Also because I can. The refueling stop was just the first example I could remember I had so I could make a quick screenshot with a single headed train.