Two good reasons spring to mind at once.

The heterogenous indigent multitude, everywhere wearing nearly the same aspect of squalor.

Denser, more consolidated materials discharged at the disposal site, excavated by mechanical means (ie., clamshelled) descends more rapidly to the bottom and deposits at a density near to the in situ density at the dredging site (SAIC, 1987a/b).

The capsule of gold−beater's skin, in which the grubs of the Cione are enclosed, divides itself, at the moment of liberation, into two hemispheres of a regularity so perfect that they recall exactly the bursting of the pyxidium when the seed is distributed.