James, Read most of the 'answers' to date . . . boy, are 'we' a cynical bunch !!
The definition of 'tip' - to me at least, in a restaurant environment - has been 'To Insure Promptness'. I do agree that many people EXPECT a 'tip', and even almost DEMAND it, though the service given was/is piss-poor.
While I admit to being a 'Certified' cheapskate, if your ENTIRE statement is true - I would definitely offer some kind of tip.Disregarding the UPS / FedEx types . . . your 'industrial' trucker is typically a 'drive & dump' when it comes to residential deliveries. His responsibility ends when the 'liftgate' touches the street. If the person maneuvers the vehicle up to your 'off-street' garage, or uses his or your equipment to move the item from the street to your garage, he is going 'above & beyond'.
For a single 'container' that I could lift or move with a handcart {say a max of about 200 lbs}I start at maybe $5.oo {TOLD you I was Cheap !!} For an entire PALLET - let your conscience be your guide and offer what YOU think it's worth. At the very least offer a cold {or hot} drink. It's up to the delivery person to refuse.
Regards, Ron Magen Backyard Boatshop {PS - I worked my way through High School on the back-end of an applience delivery truck . . . learned how to carry refrigerators, on my back, up flights of stairs to narrow for the hand-truck . . . 3rd floor & above !! THEY were usually the MOST tight-fisted and taught me the REAL value of T.I.P !!}