We'll never understand what compels customers to be rude for no reason. It's clearly some unfortunate manifestation of whatever inner turmoil is boiling beneath their surface. That being said, this particular customer decided to give some perfectly kind and helpful warehouse workers a whole lot of attitude, when he went to pick up his couch. So, they decided to approach the situation with some nice malicious compliance. Can't imagine what that customer's face looked like when he realized his new couch had flown out the back of his truck.
Check out another tale of malicious compliance with this manager who tried to fire an employee for following the rules, right before it backfired in glorious fashion.