I thought lots of herbevores have cubic scat? elk come to mind immediately but....

Fantastic question!
A lot of herbivores have pelleted scat, but spherical or cylindrical shaped pellets are the more common shape. Now these pellets may get smushed so the sides appear flat, but the naturally flat sides of cubic wombat scat are (as far as I and my books are aware) unique to this burrowing teddy-bear of a marsupial.

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  • Wombat scat (WikiCommons)

Here we can see the spherical balls of highly compressed vegetation in black-tailed jackrabbit (Lepus californicus)scat. (x)
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Now elk (Cervus canadensis) pellets are not as tightly packed, and the round pellets may have some variation in shape although they generally have a dimple on one end and a point on the other. The moisture content in the pellets means they tend to stick or even mush together depending on the individual’s diet. (x)

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These are of course just a few examples. Some herbivores, like domestic cattle, don’t have pelleted scat. Some pellets are tightly packed coco-puffs, and some are crazy little cubes. Scat is everywhere, and it’s a pretty awesome way to find out what animals live nearby. Why else do you think Zoologists are so obsessed with their scat charts?

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