for the airline i work for, i couldnt imagine the flight crew queueing for the toilets in economy, chatting to the stag or hen do about wheres best to go clubbing in ibiza! Flight crew use the fowrard toilet not only to skip the cue but to avoid the majority of passengers to ensure safety so ask a question, why is first/premium cabin at the front of an aircraft and not the rear?
so as safety is an airlines primary concern, lets all stick to the toilets situated in the cabin in which you are sitting hey.
Regards
Ian