i had exactly the same thought, i dont believe for 1 minute anyone doing this simply for sexual fun would leave someone alone for 20 hrs.
anyone into bondage for a bit of kink in the bedroom wouldnt go to that extreme they're in it simply for the fun at that time and 9 times out of 10 they wouldnt even know how to go that far, and anyone who's more advanced knows not even to go there!
someone who's already experienced or has researched thoroughly knows exactly what they're doing and the most likely outcome.
im with ashtonDS and believe that people come forward and that education of some description for the general public is needed, not practical education ie shibari lessons or use a gag correctly, but in a way that shows we are responsible are aware of the risks, dont take stupid risks take all precautions seriously etc and that idiots like that are not even a part of the BDSM community/lifestyle and that we totally oppose and condone such practises and people and do our best to educate and help each other.
although thats sometimes a misnomer in itsself, it tends to get twisted by joe public and we're criticised for 'encouraging' wickedness,sin dragging others into our depravity and the like lol
im not putting across what im trying to say too well lol