I get that part, but it doesn’t seem particularly adept at performing this function, given the pressure and the volume of the water. A sink seems like a much better functional means of accomplishing the same thing.
A bit of a WAG here, but maybe it’s the fact that the form of the… … face bidet … is the same as the regular drinking fountain so they can use that instead of a sink that sticks out from the wall without using a different porcelain form?
Try this experiment. Brush your teeth and then spit in a dry sink and watch the toothpaste stick. Now, have the water running and spit into an area of the sink where the water is flowing and it won’t stick.
Also, with this, you don’t really have to aim as long as it ends up IN the general area.