Well I couldn't do my workouts without a gym of some sort. Hard to find hundreds of pounds of resistance attached to cables I can align with muscles I want to work, just lying around the house (though now I transitioned to a home gym with a Beyond Power Voltra, and now that is lying around my house! But as I mentioned in the other comment, living spaces in Tokyo are small, so I paid a lot to get the most space-efficient setup I could come up with, and even with this I still envy some of the specialized equipment available at good commercial gyms).

It really depends on what kind of workouts you're talking about and what your constraints are outside the gym. Though I acknowledge many people are just on autopilot, get gym memberships they won't really use effectively, and waste their time and money.