Hard to find a meatless dish
It’s not that it’s impossible to find vegetarian-friendly dishes in Japan. In fact, there’s a high population of Buddhists in the country that avoid meat and even certain kinds of vegetables. However, most roadside restaurants and market food stalls offer, at the very least, different kinds of seafood.
So, if you’re a vegetarian or a vegan, you need to be extremely careful about what foods you eat. At the very least, you should assume that the broths in soups or noodles contain pork or beef. However, you can always rely on a smartphone app to direct you to the nearest vegetarian/vegan-friendly restaurant while in Japan.