That's a bit uncharitable. The choice is rarely as clear as that. It's often hard to know whether an affliction is serious enough to warrant immediate attention. So the person must weigh the risk of delaying immediate treatment against the inconvenience and embarrassment of an unnecessary ER visit.
It will be really nice when everyone has access to a medical AI that can assess these things instantly wherever you are.
Japan has a nice system: when you're not sure your issue is bad enough to call 119 (Japanese version of 911), you can call 7119 which will tell you if it's really an emergency and you need an ambulance or if you should just rest and see a doctor in the morning.
We have similar in the UK (NHS 111) - but because they're rather err on the side of caution, they usually refer you to A&E anyway.
They do seem to have some sway over the GPs though - Rather than A&E, they've refereed me to the Doctors instead. When I said it's impossible to get an appointment 111 told me to tell the Doctors they've referred me. At that point the Doctors seem to _have_ to see you the same day.
It will be really nice when everyone has access to a medical AI that can assess these things instantly wherever you are.