I will rearrange within the same bin if the placement is wasteful, which is very often in winter when coats are splayed out flat rather than placed on top of luggage or at least rolled up. In my mind we all have a shared responsibility to move efficiently and try to fit as many things in the bins as possible. But I can't imagine moving items to a completely different bin without asking, you do not know what is in there, yes it is the owner's 'fault' for not keeping valuables with them but you could still cause someone a lot of unnecessary panic.