Because of the fish and characters. While you din there they have music and videos playing. On big screen inside restaurant they have movies and toys on display.
Naruto, by its literal meaning, refers to the fish cake roll in cup noodles or Japanese ramen, which is the favourite food of Naruto (the character) and the author. As you can see in the pic, naruto is the white round thing with a pink swirl pattern inside, made from fish and so on. Usually it is called narutomaki in Japan. The affix maki means roll (卷).
Because of the anime
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