Well, I've been known to. My work laptop has a fingerprint reader to be used before it will boot, and I did a spot of very amateur bricklaying a few weeks ago. I borrowed/hired the mixer and barrow from a guy at work who lends them out at £10 a time to his colleagues, so I'm obviously not alone. The majority of those people will also have readers on their laptops.
That said, I didn't have any issues with the computer after three days' solid brickying. What really screws it up for a week or two is when I go square-rig sailing - lots of hauling on big old-fashioned cordage and my hands go glassy-smooth :-)
Pete