We also have a Y membership and are not planning to cut it out, even with FIRE in mind. It's a wonderful place to spend a few hours a day, they have childcare included, plenty of kids activities, free gourmet coffee early in the morning, heated pools, sauna, steam room, group fitness classes... Given the potential for loneliness in FIRE since all our friends will still be working their day jobs, it's a good thing for us to spend money on (I learned this the hard way after I began working from home and needed socialization for my sanity). Makes sense since DH and I were gym rats in college, we'd often go 2x/day, and the Y is the only fitness center in our city that comes close to the great facilities we had access to in college. It's $111/month for our family of 3 and we're including it in our FIRE budget.