Tipping is weird. Why, after all, are consumers responsible for the livelihood of people who are working? Back in my youth, when I worked the counter of a Mexican restaurant (Taco Grande–I loved the food. That’s why I worked there!), we certainly didn’t expect people to tip us. Nowadays, however, there are tip jars on counters virtually everywhere. I’d rather pay a bit more than have to contend with tipping.
Which brings me to Japan. There’s no tipping there, and if you were to leave money on the table at a restaurant, you would probably be chased down by the waitress to give it back. Instead, there’s a service charge at fancier restaurants, and hotels automatically added to your bill, generally of about 15% to 20%. Cheaper places, however, don’t add service charge, for the simple reason that no special services are provided.
You can read more about tipping in Japan at frommers.com, where I am quoted about policy.
https://www.frommers.com/tips/money-and-currency/tipping-in-japan-not-a-thing