"Scatter on spline" that would make things laying on their background?

For example in shape splatter I have scattered things sort of sampling the background and residing on top of it . In "Scatter on spline" all the things are laying on a plane. I tried both "spline height multiplier" with "spline sample height" node before and "heigh input multiplier" but both just send things beneath the backround.
Not that I couldn't do it separatly with black background in "scatter on spline" node but still wonder am I missing something and there is an option to do it in the node alredy?

