They cant mate because of safety the owner of the machine and supplier has to make sure the hopper can not be opened when the machine is running, it would be to easy if something was dropped into the hopper for the operator to open it and try and remove the item. Its a 13mm nut because people dont walk around with a spanner in there pocket . Yes they could have a cut out but this adds cost which would have to be passed onto the consumer.
you cant fit a quick release system with out fitting either a cut out switch or a locking system . the problem with cut out switch they can get dirty and fail so you will have to go with a locking system . if you dont do either of these the machine will fail our european safety certificate whitch pft work hard to make sure all our machine achieve this cert .