Indeed, Flash2001,
Also when the concept of power outlets was introduced, mobile pone chargers and the like had barely been invented. As technology improves, more airlines will require this stuff and aircraft will be fitted with suitable outlets I'm sure. Let us not forget that the manufacturers know their aircraft far better than we do and if they tell us we can't use the current type of outlet for reasons they were not intended for, then we should take the responsible attitude and do as we are told by them, and if we can't do that we are in the wrong industry.
My advice to all is before you plug any commercial bit of equipment into any aircraft in any way, go and discuss the matter with your Chief Technical Captain. He will have access to the engineering manager and the aircraft manufacturer and will be able to, thus, get an answer of yes or no.