I'm sure this has been said a few times, but selling runs for gil is acceptable and honestly useful for some. The line is at real money. I am aware of the fact of people selling runs for actual dollars, just like there are those who sell houses for actual dollars as well, at least on some servers. That should be a bannable offense, and might actually be already. But if all they're asking for is in-game currency for in-game work that the game itself literally spews all over the place, then great. It is no different than paying for any other in-game service legitimately, so go crazy.