I feel like "why not" is not a sufficient answer, especially when trying to explain a single object. The pharaohs were buried with everything, including people, so that's not a great analogy.

From the article:

> Archaeologists have recovered dodecahedrons from the graves of men and women, in coin hoards and even in refuse heaps, so a blanket explanation for their use has not been found.

There's no indication these were the only things in graves that I can see.

You could easily find information about Roman burial practices. It would help you decide whether knitting accessories fit the pattern.