Re What exactly do people go to emergency departments for if not emergencies ?
Its because they can't get to see doctors at primary care. In the Brit NHS access to primary care / GPs is basically rationed by bureaucracy. In order to see a doctor you have to jump through complicated administrative processes that typically require the patient to be intelligent, well enough to be able to handle the processes and have plenty of spare time.
The reason for this, of course is that Brit health care is free at point of delivery and theoretically unrationed, so the demand is almost unlimited. Supply, on the other hand, is very limited. Any kind of overt rationing is politically unacceptable*. The result is rationing by bureaucracy, since no-one can think of anything better.
Not that anyone has chosen rationing by bureaucracy, its just all that anyone can think of to control the demand. The alternative might be doctors booked up for months ahead, which is equally ridiculous.
*Its politically unacceptable, because Labour (=vaguely left) governments have a big soundbite of 'the evil tories are trying to destroy your NHS', so daren't be seen introducing demand management themselves, whilst Conservative (Tory=vaguely right) governments are desperately trying to avoid looking like evil tories destroying the NHS, so won't do anything either.