Right before being assigned your first assassination in Dishonored, you can pick up Piero's Workshop Key next to the Hound Pits Pub. Due to the harsh nature the game has in regards to some choices, and as there's a sidequest later in the game where Piero and another character are hiding in his workshop, does picking up this key have any consequences at that point? Or will you still find Piero and his friend safe in hiding?
No, it does not. I've played through the game three or four times, and I remember picking it up only once. Made no difference as to the endgame. At that point, there is a different way in provided, or one can simply use the key.