As a developer of bush strips and small GA airports. I’ve often run into grass sprites popping up in places where it shouldn’t be. The placement of the procedural grass sprites is currently based on surface type and coloration. Surface type uses a low quality bitmap which can lead to choppy artifacts (see picture below) and the low quality also means its not very accurate often leading to the grass removal to be offset to the aprons that have been placed by about half a meter to a meter.
Colaration can also be unreliable as the range in which grass generates is quite wide.
both of these means that control over where grass is displayed in your scenery is very limited. ultimately we need more control over it. Ultimately id love to see controls like the vegetation controls for polygons be implemented. But a grass exclusion option for aprons (which would have the same effect to grass being displayed as placing a concrete or asphalt material apron) would go a long way to gain more control and make sure dirt runways and roads stay dirt and not beige area’s covered in grass.