Bun disequity

Here's something I've wondered for a while (it doesn't keep me awake at night or anything, I'm not quite that sad) - how come hot dogs come in packs of either 4 (for the fatter ones) or 10 (the skinnier ones) but the buns come in packs of 6? What is that about? And regular sausages (not frankfurters) come in packs of 8, so that doesn't help either. Who decides these things?