It's simple, it's just like printing cash to pay off national debt, which only leads to inflation. If Gree were to produce a building that paid out gold, then the gold prices of everything would go up, then a modifier would be offered as a prize to have that building make more gold, then the prices of everything gold would go up again in a never ending cycle.

It's worked that way all along. I don't see this happening, and if it did, I don't see it making any meaningful difference. Anything requiring gold in the game would inflate exponentially, and this building would simply be the new Tapjoy.