I have to go -1 here, sorry. The main reasons have already been addressed. But also because you can already somewhat "sell" your tokens, it's simply not that easy (which I think is fitting). Take the ava launcher. You can get one for 10k tokens and then try to sell it. That's tokens vs. rupees. I've seen plenty of players who don't have enough tokens for a residence biome change. Well, all it takes to help them out is getting (temporary) admin status on their residenc. You could consider offering that up as a service. For everything else it's simply waiting for new features to come out.
aikar has said very plainly that tokens will never be redeemable for rupees. its intended to be a separate economy
