Unlike in the West, it's not uncommon to never visit a friend's home in Japan. This is because homes are considered private areas in Japan, and people highly value their privacy in the country. People in Japan usually just go out and do things in public when they're hanging out with friends. This might be one of the reasons there are so many public venues in Japanese cities, such as bars and places to sing karaoke.
This is also worth remembering if you're visiting Japan and a friend doesn't invite you into their home. It's simply not something that's as common in Japan as in the rest of the world.