It'll be a rare occurrence. There are always going to be players who do things like this. It's the equivalent of saying why "have money in the game if there are going to be credit sellers?" in some respects.
It's a completely hypothetical though since fd will never separate the modes and if they did for somethings it would pretty much be a non issue.
I didn't say separate the modes, I said separate the leaderboards. I think that's potentially workable. They will most likely never lock the modes, no, thank heavens.