The Reason worker throw luggage the way they do is due to airline corporate pressure, not employee laziness

They are given strict time limits to unload, load and deliver bags to baggage claim. They are also held accountable for missed bags and damage claims. So they basically have to hammer throw that shit in there or they will get punished. https://www.quora.com/Why-are-baggage-handlers-openly-rough-with-bags-in-front-of-passengers