You might be thinking of Kei-cars. One of the benefits of such cars is they do not require a dedicated parking space. From personal experience I can assure you

You might be thinking of Kei-cars. One of the benefits of such cars is they do not require a dedicated parking space. From personal experience I can assure you Saitama requires a registered parking space, I registered it myself. The dealer would not release the car to us until we could prove the registration.