The beef I have with people who blather about "catholic culture" -- e.g., in reference to the ideas and stories of Lewis and Tolkien -- is exactly the same beef I have with Fundagelical Christians who approach all imaginative works with such trepidation, unless they come all laid out in an approved, "safe" (= theologically clear) fashion: both mindsets refuse to allow for the upper harmonics.
Both the "catholic culture" types and the fundagelicals want all literature, art, etc., reduced to the carriers of single meanings in a 1:1 ratio to their root meanings. This means that. That doesn't mean they're allegorists, though allegory is congenial to them. It means that they don't like to have to sort through multiple allusions.
For instance: the Book of Revelation has many images, all of which must be understood on four different levels (the proximate, the prophetic, the perennial, and the personal) at all times. It's like reading poetry chock-full of echoes and allusions, or listening to polyphonic music. All of the multiple levels are there by design, and they add greatly to the meaning of the work, and also to the enjoyment (in all senses) of those equipped to receive it.
In a book of fiction, various characters will exhibit traits of good and evil, act out echoes of saints and heroes, be like and unlike Christ, etc. The Cauldron of Ceridwen, the Holy Grail, the eucharistic chalice, the dish of blood that Dindrane bleeds to save another, the wounded Fisher-King, the Elves' lembas and miruvor, the habit of the Martians of eating their loved ones (Stranger in a Strange Land), all fold into each other and reinforce each other, make us think in particular patterns. The actual meaning of a particular act, along with its historic referent and our own committed belief, may be the greatest presentation of that image, or rather, that image may most perfectly express that idea, but still, the presentation of one does not eliminate the others.
A harp or guitar string vibrates not only according to its length, but according to all its harmonics. The thirds, fifths, etc., are all there, adding to the sound of the plucked string. If you eliminate the harmonics (say, electronically), you may get a "purer" sound -- the sound of that single note/pitch only -- but you impoverish the experience of hearing that note.
Purists of every stripe tend to be reductionists. They are so concerned that we get the "right" meaning from each thing, or that the "right" idea be singled out (and all the "wrong" ones be set aside), that there is no room for the ambiguity of normality. And this is profoundly at odds with the idea that Christ became a real human being.
To be human is to experience all of reality in all its relatedness. Yes, we know what good is, but we still experience evil along with good. Yes, we know what health is, but we still know weakness and disease. Yes, we know what life is, but "in the midst of life we are in death." Yes, we know what sanity is, but we are aware of our own neuroses for all that. Yes, we know what love is, but as they say over on Facebook, "it's complicated." We believe that Jesus of Nazareth did not sin, saw no corruption in death, was perfectly and radically sane and all the rest of it -- but still, he saw how complicated life is, and his character was as multi-faceted, his words as shaded and double-sided at times, and his experience of life as full of levels and nuance as anybody's. To be whole is to be aware of more than just each thing as itself.
I can understand the necessary drawing of distinctions between right and wrong, including right and wrong ideas/doctrines. I can desire to belong to a Church that defines and defends the right ideas, and I can accept her authority. But even so, that is not the same thing as acquiring the theological tin ear that some people think is the mark of the religiously mature.
As Charles Williams constantly stressed, "Neither is this Thou" must always allow for "This also is Thou." One can follow either Way, the Way of the Rejection (one might say, also, the Reduction) of Images or the Way of the Affirmation of Images. But still, both Ways must show courtesy to the other.