I belong to Folio Society. I've belonged for probably about 10 years. Periodically I will say, "Oh, it's such an expense to be expected to buy four books that run at least $50 each" (they have a requirement that to remain a member, you buy at least four books in a year), but I wind up getting drawn back in every year - and buying all four at once, because that's how you get the free books, and some of the free books they offer are truly marvelous (and even if they're ones I don't want, I can donate them to the campus library - they have benefited from several of the art books I've gotten that I decided took up too much of my personal shelf space). This year it's a huge Jacob Bronowksi book (The Ascent of Man) and I JUST remember some episodes of his PBS series, so I think that's one I will keep to read myself.
I wound up ordering "At the Back of the North Wind," (which is a sort-of-folklore, sort-of-allegory by George MacDonald. I've never read it but have wanted to. And now I can have a big fancy edition with nice illustrations!) and a book of medieval comic tales, and a history of the Restoration (which I've begun to realize I know very little about), and a book called Empires of the World which is about human culture and its development (Keeping with the book I'm currently reading, in a way).
The books are very pricey and they are really the one true luxury I allow myself. I don't take lavish vacations or eat in posh restaurants (in fact, a lot of the time I eat what is closer to "peasant" food, but that's what I like) or buy $300 pairs of shoes. But big, lovely, fancy hardbound books - yes. That's my luxury. They're what I think of as PERMANENT books, as in "If I were moving somewhere and had to reduce my library by at least half, what would I keep?" and they would be a big part of it (So I generally try to choose books I either love and want to re-read multiple times - I have a copy of The Hobbit and also To Kill a Mockingbird from Folio. Or I choose books that can be easily dipped into at a variety of times (all the various-colored Fairy books. And I think there are still a few more they "need" to republish - I think there was both an Olive and a Grey Fairy Book, but they haven't republished them yet)
And I really have the feeling that I'm running with an exclusive crowd, when I placed my order, the dropdown menu for what title I wanted them to use for me included "Lady" as a choice. (I could "legally" and correctly choose Miss, Ms., or Dr. I actually wound up going with Miss. I tend not to publish the fact that I'm "Dr." outside of my academic realm because most people when they hear you're Dr. Lastname, they assume you're a medical doctor, and that can get awkward.)
This is probably the only situation in life where I belong to a group that is also a group Lords and Ladies belong to...