This torture device is present in most Spanish households. It took me a while until I figured out what it is.
Then I saw the same thing in restaurants with a pork’s leg squeezed into it.
Ah, so that’s what it’s for. They have a big, sharp knife next to it and cut pieces off it as tapas. Or to put on the tostadas for the meat lovers.
And since we don’t eat meat we hadn’t seen it in practice until recently.