In general I ride on the street and avoid bike paths unless it is a really obscure time, the cyclists are more dangerous than the cars in my view.
That said, I do ride regularly on the sidewalk on my way to work. There is an unavoidable section where conditions and traffic provide no room for a bike. The city could care less.
I could push the issue but the traffic zips by near 50 mph (40 mph zone) so level heads prevail and I ride the sidewalk for that section.
Now, with riding a bike one gets a renewed lesson on why drivers of autos should signal and do not. Or do dozens of other stupid things. Much of this behavior can be anticipated but requires effort.
That guy or girl at the stoplight next to you texting or on the phone? They will be bad news if you assume they will stop when the light changes.
Driver's head visible in the parked car ahead? That can be a door in your face.
So, awareness is learned. Anticipating stupid people is learned too. It will become second nature. The Sidewalk is sometimes necessary. Yield to pedestrians, its good karma.