It seems logical and pragmatic to me. They did indeed care for the graves: they replaced all the wooden markers and then they updated the marble ones to conform

It seems logical and pragmatic to me. They did indeed care for the graves: they replaced all the wooden markers and then they updated the marble ones to conform with standard practice at other sites. Anyone who visits graves knows that upright markers were deprecated long ago when they discovered how easy it was to run a mower across flattened ones. The article implies that the bottom halves weren't inscribed or differentiated, and so in retaining the important half, the graveyard was cared for indeed, and $45 was earned on their sale, and someone now has a memorable home. I would argue that the home isn't made of gravestones, since without markings they again became ordinary marble slabs. (Disclaimer: I am a Catholic who venerates holy relics and finds charnel houses fascinating.)