You must have led a very sheltered life if you have never seen adults unable to use cutlery correctly. Stabbing food with a fork, head as close to the plate of food as possible to shovel pasta in, spearing chunks of meat and eating round it like a lollipop.
The dinner ladies at school were shocked by the increasing number of children who ate with their hands, including wet food like stews, and even some who attempted to lick their plates clean.
Just laziness on the part of the parents, plus the fact that many families eat off trays in front of the television.
As a species we have brains which enable us to design then use implements with our hands which makes life easier.