As a humble non flyer my main point , by declaring an emergency if the circumstances are correct then we can give the instant aid of 'SQUAWK 7700'. This aids the ac, the ATC unit and any other units in your path. I appreciate that there are times when things are not right, and you would just feel better if there were people aware, however more and more aircrew seem to prefer to sneek back and hope that they get away with it. A broad statement but how many of out there have done it.