A certain major distributor sent me this trimmer the other day 

There is a reason for large over sized packaging.
Small items are regularly sent in over sized packages to prevent them being lost due to their small size.
For instance the package slips behind a wheel well of a delivery van and is overlooked.
So the larger packaging is preferred over the possible hassle the loss of a package creates.
For instance when a delay of the part arriving is more expensive than the extra packaging.