I dunno, thinking about it in terms of "spiritual system" applying in general, and "spiritual" applying to a specific case does not seem like a conflation, in the same way that "set" and "element of set" are distinct.

Not all things referred to in a spiritual system need be spiritual. For example, a spiritual system could say that drinking is not spiritual -- which is what Islam explicitly says. Indeed, associating the tag "spiritual" or "not spiritual" to different activities is one of the main goals of religions.