These type of stone coffins saw use in the Middle Ages and were designed to be reused. Only those with wealth and/or social standing could be interred in one of these and they came in many sizes. The cadaver was left until the soft tissue had decomposed [hence the very real need for a drainage hole!] and then the skeleton was reburied and the next occupant placed inside. Some of the coffins were within the church buildings under the floor and so the story does that this is where the phrase "stinking rich" comes from. It is very dubious that this is really the case though. By the time of the reformation burial practices had changed and all bar a few were buried inside.