I use in bathrooms all the time, just snorting of course. It actually presents a little bit more of a challenge because you need a flat, non-porous surface, large enough to break out a line. I always carry alcohol swabs to wipe the surface and if the surface is particularly questionable (which most are) I'll wash it down with soapy water first. I also had a lamenated 4x6" card that worked well to break up drugs on.
Definitely a high demand for one person BRs, too, much preferred. Also help if you have to whiz because it takes me a minute to go when high, and if someone is in the room with me its like guaranteed stage fright x10,
I agree with the BR causing cravings. When I go in certain ones I used more often than others (like the one at work) while being clean and all I am thinking is how I'd love to be getting high in there right now. Aside from my bedroom where I do my stuff when at home, that bathroom at work is probably #2 on the list of rooms I have used in the most. As for using at work, lets just say its better than withdrawing at work, which causes me to be a clumsy, uncoordinated wreck.