Several of mine sure have. Even with electrical tape wrapped around the seam, moisture gets into the microswitch and not only keeps the light from turning off, but occasionally turns the light on as well. I noted this once on tour when its flashing woke me in the middle of the night. THEN it wouldn't turn off till I took the batteries out.

It was dark when I fell asleep, so I'd have noticed if I'd left it on. Also, nobody around who would have turned it on as a prank.