While it is a waste, it is necessary not to let things like that slip. They built something they did not have a permission for, as simple as that. Just like when you decide to expand your home with an annex without a permit.

They got permission to build a house based on plans A, and actually built a house based on plans B. And by the looks of it, we are not talking about the building being 5cm to wide in one direction (which had led to a tear down order here in one case), but quite a number of massive violations.