They need heat to stay alive, which might have given them the needed edge on a tanning bed (which is really a long shot to begin with), but once you get below normal body temp they start to die fast, particularly on an unprotected hard surface.
Or he got them from somewhere completely different!
I swear though, P&H, this is exactly something that would happen to my friend (the one who had crabs that time). Go to the tanning bed to get rid of one thing and end up with another. One time he opened a door over his toe, and ended up with some sort of crazy infection moving up his leg. Things like that just happen to him. Luckily he's a great guy (and if you ever need a T-Mobile phone in Asheville he's the man to see!). But the story of your friend totally reminds me of him.