Out of respect for Japanese "omotenashi", I won't call it greed... I do think most Japanese people would want to maintain a fair and equal pricing structure for all customers. In a better world, if the economy was booming and people were prospering, there might still be some establishments looking to earn more by fleecing and overcharging tourists. It's fine to call that greed, or taking advantage of demand inelasticity, or whatever.
But... here we are. Times are hard, I get it. Even with overcharging under a dual-pricing structure, tourists will probably continue to visit Japan if they can afford it. It's just a shame that the Japanese will probably have to compromise on some aspects of their omotenashi because of greater factors beyond their control.
Maybe by having a dual pricing structure, they'd be able to realize maximum profits. But not everything is calculable in dollars and cents... all you'd need are a few establishments to start vastly overcharging tourists for whatever cooked up reason and the reputation of Japan for tourists might soon become "nice scenery, nice culture, but the people there will overcharge you because they think they can exploit your ignorance, or just because they can..." - neither of which paints the Japanese in the best light, or the way they'd want to be seen, probably.
I'd absolutely add a tourist tax to all purchases. I can't imagine what it's like watching your country turn into a playground for wealthy foreigners while you're struggling.
Or they're going because now is a prime opportunity to visit on a budget. A tourist tax could mean some visitors staying for less time or deciding to visit somewhere else.
There are many places on earth that exist largely because of tourism. And encouraging people to go experience cultures outside their own is a good thing.
If these things were not available to the public, then they would not be considered usable, and would therefore be exploited into nonexistence to make them usable.
I'm not saying tourism is the best solution, but unless you are hiking to the middle of nowhere or a city, there's a decent chance tourism is a part of the reason you can enjoy that hike at all
As a New Orleanian, I can very easily imagine what it's like to live in a struggling economy while wealthy vulture tourists flock to take advantage of our food and culture. Some of them like it here so much they get their equity partners to buy up all the housing for AirBnBs. It's so great.