Is it common to see non-words (like the homophone verticals in this answer) used in English crosswords? Ignoring abbr., initials, odd names, various symbols, "Xth and Yth letter", "middle of X" and other similar simple fillers.
Was that particular puzzle just extra cryptic (for fun/art) or is this common?
I would say they are rather rare. This was a special puzzle-note the book title. I have seen cases where there is a symbol like star in a square, but usually (if you spell it out) it makes words. I have also seen cases where a few letters are deleted from theme answers. Maybe the theme is POSTHOLE and the letters POST are deleted from the theme answers making non-words.
