[angiosperm]

It has been quite common to believe that all the personal property of any dead person was unsafe or unclean to use, and so was often burned or buried with them. This was observed, for example, in northern California tribes in historical times. Sometimes it only applied to weapons.

It doesn't depend on a belief in the afterlife. What archaeologists call "ritual" need have nothing to do with religion. Washing your car and mowing the lawn are American suburban rituals. Halloween, Christmas, and birthday celebrations are ritual. We also have ribbon-cuttings and graduations. When I was growing up we "pledged allegiance" to the US flag.