> Because what are the odds that the place which incurred the expenses of educating you, out of the hundreds of competing muncipalities, large and small, near and far, naive and sophisticated, meibutsu vs trips vs gift cards, high or low, will give you exactly the right thing and win the competition, and this will happen in almost every case and produce the same net flows as simply sending the rebates to, say, people's registered birthplaces?
I would estimate those odds as near 100%. I assume you can choose what services you'd like to receive, simply because not everyone needs a grave maintenance service -- and if you do need one, there is no way to get it without specifying the particular grave you want serviced.
The OP explicitly states as much:
> A number of cities in Japan, including my adoptive home town of Ogaki, have made this offer: for a no-cost-to-you donation of $100 or more, the city will send someone out to any grave in the city limits. That person will clean the grave, make an appropriate offering, and send you a photo. This is a beautiful thing.
> Most of the gifts are more prosaic. Locally produced food is very popular. If you miss the taste of home, they’ve got you covered.
> Cities partnered with local firms to handle the e-commerce aspect, and eventually with platforms to bundle many different items into a single donation; think of it as a shopping cart you could fill with donated money.
This isn't a system where you have to buy a poorly-optimized bundle from the town that happens to offer something close to what you want. You send a donation and you can choose the return gifts you'd like to get back from among the services that town offers. And in the steady state, all towns will offer cash equivalents for people who want them, as well as more hometown-specific services (which have a higher profit margin!) for people who want them.