One thing many people don't know, in Japan you can bring any food or drinks you like though security on domestic flights. Not an issue whatsoever. You can also bring your own beer / ChuHais on the plane with you from the airport convenience store and drink them just like any other soft drink you'd bring. Airport shops don't gouge on prices for food and drinks, so maybe the airlines feel less necessity to provide it since prices in the airport are extremely reasonable. You can also bring your own food into the lounge and eat it there while enjoying your complementary drinks.

It's very different than a US domestic flight where you can't bring outside drinks inside the secure part of the airport and vendors have been given the freedom to charge as much as humanly possible for drinks (and food) airside. I've always felt that concession prices should have been heavily regulated post-9-11 when security stopped allowing liquids. But in Japan thankfully you don't have to worry about either.

Lastly, domestic terminals in Japan are extremely efficient, so you don't need to be there hours in advance like in other countries. You could bring something to eat / drink on the plane and spend well under an hour in the airport overall.