So lately at the gym I've seen quite a few people loading up the bar with a lot of weight and not doing the lift with a full range of motion.

It seems the squat and bench are the most common. They'll load up 300+lbs and only go down maybe 6 inches (IE squat - not parallel, bench half way down not touching their chest)

Is there any benefit to doing this? Seems kinda half ass to me and more like trying to show off.