You can hide your anchors on grounds using the 'foreground' option. To achieve this, you need two dynamic grounds anchored together, like so.
The ground with the LOWER Z value should be set to FOREGROUND.
The ground with the HIGHER Z value should be set to BACKGROUND.

The anchors always show on top of the ground with the higher Z value than the one to which it's anchored. But when the ground with the lower Z value is set to foreground, it sets itself in front of the other ground. The anchor appears on top of the ground with the higher Z value, but the foreground with lower Z value shows on top of the anchor.

Example Map: Code for TribeHouse - @585040 | XML Code for Editor