^I agree with you there. But I live here and eat traditional Japanese food just about every day, so I feel justified in eating hamburgers or pizza or other foods every now and then. And, even so, what you may consider Western food in Japan is actually Japanese food (just like spaghetti is American food).
Japanese pasta, of course, comes from Italy, but I had mentaiko pasta for dinner last night. That's salted cod roe spiced with red pepper mixed in pasta noodles with dried salted seaweed on top. Completely Japanese food. I also had a soy-sauced based spaghetti with seafood, seaweed, and a raw egg on top last week.
Or curried rice. Japanese curried rice is not Indian food, no matter how you look at it. Of course, curry originally came from India, but the way it is made and eaten in Japan is very different from the way it is in India. Besides, curry being one of the most popular foods in Japan, it is similar to how pizza is American food, even though it isn't originally from the US. Pizza is also Japanese food, by the way. And Japanese put toppings on their pizzas that most Westerners would find very strange (like mayonaise, corn, potatoes, various seafoods such as cod roe or crab, sausage, asparagus, eggplant, tartar sauce, Korean-style meat, green onions/leeks, etc.)
When my best friend comes to Japan, I'm just gonna give him real Japanese food ("traditional" Japanese food?) like okonomiyaki, takoyaki, tenpura, kaitenzushi sushi, tonkatsu, Japanese-style Korean food, tenpura, etc.