I'm not saying OP was justified in doing so, but when you're working with heavy weights, you cant always lift them into your starting position easily or put them back down gently after a set or three of them for that matter...
75lb's? Unless he's pretty small, no. but once you get into the 150+ range...you are bulking up major muscles, not the smaller untrained muscles involved with the motion of picking up or putting them down. You can handle a lot more weight in the lift than you can in preparation. Why do you think there are racks for benches and squat bars?
Because NOBODY is going to finish a set of 600lb squats, lift the bar over their head, and gently set it on the floor...