As I understand it, this is for stuff that's dropped off at Bell Services and then delivered to your room. This is new from the package delivery of items delivered at the front desk like mail, UPS, etc. Most grocery delivery services drop things off with Bell Services who then bring to the room when called and are presumably tipped (at least I did).
I can see some operational demands that would encourage Disney to charge - more guests are doing this, requiring more storage space (especially refrigerator space) and ties up bell services more with deliveries.
I also see the other side, too, especially for DVC:
Disney discourages having your own car through parking fees and DME.
Disney provides kitchens to DVC members (don't have to pay for parking but do have access to DME)
Disney promotes the advantages of having one's own kitchen.
Disney now charges you to have your groceries delivered and left at Bell Services.
The work around is to be present for grocery delivery (bypassing Bell Services ) but it's another charge and a pain for those of us who don't like to be confined to our rooms for several hour after arrival.
For standard hotel guests, it may be less of a problem because most items are probably a few beverages for the fridge, and maybe some cereal for breakfast. For DVC guests, this is an extra charge to plan for.
I also wonder if Bell Services sees any of that $6? I usually tip around $10, more if they also bring my Owner's Locker. I won't stiff BS, but I will be re-thinking my strategy now. Maybe to Disney's relief if the goal is to discourage guests from having items delivered.
Dirk