Capsule shadows cast onto emissive objects

I’m experimenting with stylized shadows to allow unlit, toon characters to cast shadows onto a static, PBR environment.

Capsule shadows seem to be almost perfect for this goal but for some reason they also cast onto emissive materials, for example, the shadows cast onto the ground are correct and what I want, but shadows on the shoes and foot in the image are incorrect as those shaders are unlit and have no base color, only emissive color.

I’m assuming this is a bug, as dynamic shadows shouldn’t cast onto emissive unlit objects, and they don’t under any other lighting set up, only when shadow capsules are used.