This needs clarification. If you can gift it anywhere, can you gift it back to Tokyo (for example)? I would think that the kickback that the place you actually live (services, access to events, etc) would be more valuable to the taxpayer than would be services in a city where you don't live.
The article explains it is an opt-in program; if you live in Tokyo and don't opt-in to gifting your taxes elsewhere, you're paying all your taxes to Tokyo.
Considering it was an olive branch towards the rest of the country in order to avoid this being set into the national law, it'd probably look pretty bad if Tokyo started to try and outbid the rest of the country.
