I've known a lot of people who were paying for gym memberships. I don't know many people who have consistently made use of their gym memberships.
People in the USA know that exercise is important, and certainly that's true of your average hospital employee. But when it comes to actually getting the exercise, it's just plain easier to find the time and motivation if your mode of exercise brings you to work. For a lot of people, I think the trouble with getting exercise when you're not going from one place to another is not that it's impossible for them to find time. It's just, it isn't particularly easy to find time for exercise, and riding stationary bikes, stairmasters, and such isn't all that much fun.