Last year, for example, I spent about 3h a day walking Nice. I covered most of the tram network on foot because I wanted to see areas well outside the typical tourist areas. I could've done the same length walks at home, but I'd have seen places I've already been many times.
And often even when you go to destinations where your home might well even have superior options sometimes, the point is partly that it's different and new and that in itself has a qualitative difference in how you experience it (try walking down a street you've never walked anymore and be present, and walk down the same street again every day for a week - the experience noticeably changes), but also often simply that it creates an adventure, even if a tiny one, exactly because it's not something you usually do on top of being somewhere you usually aren't.
But my parents are part of that sizable minority of members who never go to these places on their own. So every time I visited home, there would be an appreciable pile of passes and vouchers on the mantelpiece, and Mom and Dad would encourage me to take a friend, or my sister, and have an outing with the free passes, so we could at least use them up.
So this is the case in my family. Now I can see where people who love visiting museums become members in their own towns, get free passes, and visit there often, right in their backyard. I can also see people becoming members because they love entertaining visitors and they can show those visitors a good time if they have a supply of free passes on-hand and ready for when someone new comes around.