Well, to be accurate I personally only* use it on hills, and then usually only if I'm there for a while, otherwise using behavior such as what you describe. But you can certainly tell from the way the car in front moves off whether they've just released the handbrake, and most of the people in situations like the above do.

pca

* Or in empty car parks covered in snow, mud, or other low-coefficient-of-static friction surfaces at 2AM