Most Japanese kitchens have a combined microwave and oven; the oven is consequently small compared to one in the US but works well enough. Woks are used for Chinese cooking and so aren't standard in a Japanese kitchen.
The fridges are small by comparison but, especially in cities, most people shop several times a week and so space isn't a problem.
Having a walkable city makes frequent grocery shopping much more comfortable. When I lived in Osaka there was a grocery store between my apartment and my nearest station. I only had to meal plan a day at a time, my food was always fresh, I never bought more than I needed and ended up tossing out food that I didn't get around to cooking. Every grocery store was walking distance to another grocery store, all the way from my place to the downtown Namba. Grocery shopping in the states is such a pain in the ass that I don't want to do it more than once a week, and my friends have trouble understanding why I hate car culture.
The fridges are small by comparison but, especially in cities, most people shop several times a week and so space isn't a problem.