FWIW, my insurer will cover my camera and computer equipment, but they won't touch a cell phone of any kind.
I tend to think of cell phones as disposable technology. Not surprised that they don't want a part of that. Sure, you paid $600 for that phone. Doesn't mean that it won't be obsolete in 6 months. The premium you are paying is for 'latest and greatest'. Same could be said for cameras and associated equipment. However, I think bodies might hold just a little more value over time than cell phones (which are yesterday's tech, the day after you buy it).