Many people have had experiences that fall into categories that make them difficult to speak about. Because they may not be universally shared experiences, there's not much of a common vocabulary that feels adequate.
To me, a large part religion seems to be to provide such a vocabulary, and therefore, purposefully or not, monopolize the description of such experiences. By doing so, they inevitably funnel the rationalization of these experiences into certain paths.
The reductive alternatives offered by skeptics are not usually a satisfying substitute, since they are usually not talking about the same thing. Skeptics like to shift the conversation to what they consider the objective which, while not necessarily wrong, is a different conversation, and beside the point. To make an inadequate comparison: it's like discussing the objective nature and accuracy of poetry rather than the experience of it, and the impact on the reader.
There are many other ways to look at the development of western occultism, but from the perspective of language, it seems to me that it had a lot to do with establishing a framework that tries to side-step the effective monopoly of religious conversation, as well as the only alternative offered: plain denial of the experience.
You could, of course, lump the history of occultism in with religion and say "it's not significantly different"/"it's a mish-mash of borrowed ideas from traditional religion"/etc., if painting with broad brushstrokes, but I think it was a conscious effort to break out of the frameworks set by convention and religion.
It's an attempt to take command of the internal and external conversation regarding something deeply personal.
I believe this is important, because putting language to something (whether it's words or symbols) is a hugely important way to internalize, process, and develop the results of an experience, whatever it is.