They often end up with bits of stuff stuck to them while they’re wet, like feathers, bedding, etc. Poop isn’t uncommon either. The same people who won’t buy salmon unless it has that freshly dyed pink color, and won’t buy potatoes if they aren’t universally convex, balk at the bits that remind them they come from a real place and aren’t just summoned into existence for their sake. Washing the eggs takes off the bits but also the ‘bloom’ which is the natural barrier to bacteria and the like. Hence, refrigeration.