An employer I had a few years ago stated that any electrical device plugged in at work premises would be "theft" and you would be fired and charges pressed against you. No cell phone recharging, no lamp, no fan, nothing that plugged in. You plug it in and they catch you = lose your job and get arrested. Seen the Operations Manager have security pull someone from their desk and walk them out the door for plugging in a cell phone and then putting it in a desk drawer to try to hide it.
I would never just ASSUME something like a electrical outlet or water or anything is OK to use just because you can reach it.
Would you park in someones driveway and decide to wash your car because HEY they left a hose right there where you can reach?
Would you just take a plant from someones garden because hey you can reach it from the sidewalk?
Theft is theft.