Well, there's a footnote on my end: Me taking the drives home is a bit of a grey area, as the procedures say that the drives are to be mechanically destroyed when no longer needed. It doesn't specify needed by whom. And I do attack them with my angle grinder, so it's in accordance with company policy.

And yes, my employer knows and is OK with it. We go through a ridiculous amount of drives due to large storage needs, so pragmatism tends to trump bureaucracy.