The Keymaker

In Black 2 you can catch a Regirock, and a Registeel. In White 2 you can catch a Regirock and a Regice. In these games you can trade keys to access the other uncatchable Regi. Do you think that this key system is a good idea on the programmers part, or do you think that it is just a waste of time?

-Also, off topic, can you trade keys across the wifi, like pokemon, thanks.

I think it is bad, I mean, I have Regirock and Registeel, and its just bugging me not to have a Regice.