Because it makes their table seem just as fancy as a restaurant. It is a small, non-consequential matter that is amusing in its presence and adds a bit of fun to eating.
No @Aster, not politically incorrect. I just wondered if you held married couples to a different standard than singles or unmarried couples? It must mean something for you to frame a question around it.
My male SO bought a salt & pepper set that aren’t quite 3 feet high, but pretty close. I asked him why. I think the response was that they were impressive (meaning large) and a good deal (which meant he bought them at the pound shop/dollar store).
They are awkward to use unless standing up. As soon as I get around to emptying their contents, they will be given away to a charity shop. Since that purchase, we picked out a more practical sized set of S&P grinders.
Because the want to? I’m kind of confused, there’s many reasons to buy something like that. Aesthetic being the first reason that pops up. Maybe it matches some of their other decor.