The survey is asking the wrong question. The issue is not whether you can see a doctor when you want to. The issue is whether you can receive medical attention when you need it. Of course people like same-day or next-day attention. It's part of our instant gratification mentality. But how often is such prompt attention medically necessary? There's always the emergency department or 911 for truly urgent matters. 
In my family the Canadian health care system always provided the attention that we needed when we needed it. And we didn't have to worry about whether we could afford it. It's a blessing.