Convenience stores are prolific in Japan. I found travelling in Japan was like travelling on easy mode, because you could do almost everything last minute, including travel and accommodation. There were many days there where I woke up with no plan, half way through the day decided "Ah, this city looks nice", booked my train ticket 10 minutes before it departed and booked my hotel while in transit. Restaurants shut once you arrive? Not a worry, take your pick of a 7/11, Lawsons or Family Mart and get yourself stocked up to enjoy the city properly tomorrow.

Try that in Australia and you'll find yourself in a rental car with no petrol, in the middle of no where with no food!