They have done that in my home town since at least the 60's. Around here they call it chip seal. The town was supposed to "repave" my road last year. Instead, they contracted with the county to chip seal the road. First they came in and ground the asphalt off the crown of the road. Then chip sealed it. Now, we have a divot down the center of the road that collects water. Will be a real treat come spring! Idgits!