Why do warehouse clubs require membership?

Total Wine has the lowest prices for beer and wine. The hard stuff is in a different section which I don’t visit, but I would guess it also has the lowest prices there. In addition, it offers coupons about once a month for various amounts off the listed prices, depending on the item.

I remember when there was a Price Club in Albuquerque. After the merger, I think they shut it down for a while before opening a Costco in the same area, if not the same location. My parents had a Price Club membership and I think they actually got it by piggybacking on the membership of my mother’s hair stylist. Eventually they got individual memberships to Costco and Sam’s Club.