To my eye, these are Eulychnia saint-pieana. They always look as though they are struggling to survive in habit, and maybe they are. In captivity, they are an incredibly beautiful and rare plant. If you like spines and wool, these are for you. I was given some habitat seeds a few years ago, they germinated well and have not been difficult to grow. I've only kept one of them, I wish I had kept more, although these are not the sort of cacti that I now grow.
Isn't it true that, along with the Copiapoas, they can grow in places where it never rains? They can get all the moisture that they need from droplets of sea fog collecting on the spines and dropping onto the soil.