The folks at Bloomberg have an excellent short video (see the source link) about the Kiva Systems warehouse robots used by Amazon. The Kiva robots are intended to operate much more efficiently than humans performing the same job of retrieving items from the warehouse. In addition, repetitive motion stress is reduced since there isn't as much need for people to bend over or carry heavy items.
One of the most interesting statements in the video relates to the fact that we shouldn't be so obsessed with the idea of creating robots that look like humans. As years of effort have shown, it's actually fairly difficult to achieve something that approaches human dexterity. With that said, it is far easier by comparison to create single-task robots that do things that humans can't do well or shouldn't do much of from an ergonomics perspective.
Go ahead and check out the video (which is only about a minute and a half long). I bet you can't look at the Kiva robots without thinking of them as the 'bigger brother' to iRobot's famous Roomba robots.