No I didn't spot that. I have considered that bullauns were used for ore crushing rather than food preparation, as some (ridiculously in my opinion) suggest*.
Pigment preparation is another option - they could be the Neolithic/Bronze Age equivalent of those funky paint mixing machines in B&Q.
* I know that something similar was still in use in the Shetlands in the early 1900s, but I think this was more likely to be a re-use rather than an original use.