Given that for a given feature, I simply guess which of the two amenity-points.mss and amenity-symbols.mss files it's in, that suggests that something is not clear.
If anyone has a rationale for the split between the files, then I'd love to hear it, and then change the files and layers to have more meaningful names.
I think amenity-symbols is for things that don't have names.
However, I agree with your confusion, and would also prefer a clearer separation.
Merge amenity-symbols into amenity-points
This resolves #210