If one wants to find new and creative ways to protect the environment, one only need to look at the shipping practices of the major carriers that require cocooning tiny parts in thermonuclear blast-proof packaging.
HP is almost certainly responding to the organized carnage that passes for shipping service nowadays. My consulting company has received packages similar to what is shown above via various shipping companies (name one, they are all guilty) festively decorated with punctures, huge dents, corners ripped off, gaping holes, waterlines and, yes, even tire tracks. All too often the contents are damaged beyond repair, even with extraordinarily well-thought-out packaging.
HP, which few can argue produces generally high-quality products and services, probably considers using a 1/2 cubic meter box to send a small fuser cartridge to be an investment in customer satisfaction, not to mention a cost reduction over repeatedly replacing the same item for shipping damage or under warranty when it fails early.
Interestingly, several years ago HP sent me a fragile, cast magnesium frame rail for a laptop. Not in 32 boxes, not on a pallet, not even in a small, rigid box with packing peanuts or air pillows. They sent it in a bubble envelope. The part arrived in 3 pieces. But what was remarkable was that all three fragments could be accounted for, as there were numerous holes in the envelope. The replacement rail arrived carefully packed in bubble wrap and peanuts in an oversized box. I suspect this kind of experience was the genesis of the overpackaging trend at HP.