I've been working with this issue for a while now as well and today found a partial solution - hopefully it will work for you. For my roofs, I checked cover fills on and selected the fill I wanted. Nothing would appear.
Then I selected 'use fill of surface material' and under the 'Model' dropdown made sure that a material with a fill pattern was selected (as opposed to the paint materials which have no fill type). After that, the hatch showed up in elevation.
Still doesn't explain why setting a particular fill under covers fills won't work but at least I see what I need to see now.
hope that helps!
EDIT - I've worked with this some more and it's gotten weird. I found that in floor plan (of a story I've set above the roofs) fills were shown for roofs set to 'use the fill of surface material' as well as for those that weren't set that way (which aren't visible in elevation).
But the fill pattern displayed was different for each setting - the roof set to display a material fill had a larger fill pattern.
THEN, I set a few more roofs to display a cover fill (not 'use fill of surface material) and suddenly the fill shows up in the elevations even though when I changed to that same setting while in elevation, no fill became visible.
Also, in elevation, the fill appears correctly distorted for roof placement and pitch angle, but in plan, it is not.....
very confused now....