Their response doesn't make sense. I'm sure they did have greater demand for Soldner than they had for Octodad, but what the f*ck does that have to do with people seeing it's available and adding it to their cart only to find it's sold out when they try to check out, then when they went back to the item page it was still "in stock". They can argue all they want that the storefront is great, but it obviously is a broken piece of shit.
Again, they don't care. The only thing that matters is "3200 copies sold in minutes!!!"