It's just a passive aggressive thing in my opinion. People want to say the game is doing poorly, but people would try to disprove that, so those people might go a different route than the direct one (cause then they'd have to debate it). Saying the game is going free to play at some point is saying it is going to flop. But even saying that is a obvious knock that the game is doing poorly. So it's just taking it one step further by saying "Oh hey, when the cash shop does come out, what would you want in it?"

It's twice removed, but it's still them basically saying the game is doing poorly (which while there is obviously lots of criticism, at the moment, financially it seems to be doing ok).

It's kind of like saying: "So where do you want to spend your last moments when the president causes the apocalypse?"