Re: So, THIS is a thing...
Assuming similar alloys, larger stud polepieces are going to have higher inductance and a broader magnetic field. It's pretty much a cheap version of a metal bar polepiece. Lower inductance/less even coverage than that, but closer to that than simple small studs.
Whether that is useful in the pickup will depend on the designer/winder's capabilities.
I don't know whether it'd be better or worse for pickup assembly... You'd have to orient them correctly, but they might be easier to handle than round polepieces. Probably a tossup overall? A single metal bar polepiece is probably far cheaper for assembly, but I'd expect it to cost more.