No worse than carrying around a grenade with the pin already pulled. Are people actually married to these devices? Or are they now irremovable? Even if you could be certain it won't light up, there is still a risk of it scratching your film inside the changing bag. Doesn't make sense.
Here's a story for Brad. Up there directly above Sonora Pass, I had just set up my 8x10 camera and tripod aimed at that big dark pinnacle behind Blue Lake and in front of Leavitt Peak. Then of all things, an eccentric German hiker came stumbling up the path staring at his GPS device. He almost tripped over my tripod, was startled, and asked "Vere ish the lake, vere is the lake?" The lake was right in front of him. Then he looks at my setup and scolded me, "How dare you deshecrate nature vish that big thiiiing?" I merely smiled, and replied, "Nice GPS; is that the model John Muir used?" Incidentally, one can see all the way down to the highway itself from that spot, so route finding should be easy. The fellow sneered at me, and attempted to walk the final forty yards or so to the lake while once again staring at his GPS, but soon tripped over a log. Damn gadgets. ... Anyway, he did make it a bit further to the lake, which he finally discovered by falling into it ! Luckily, it was the shallow end.