You shouldn't think it strange; in ancient times there was no photography and few artists who could paint, so stone pillars were used as a representations of a human image. They wouldn't bust after installation and were part of our culture.
不要覺得奇怪，古時候沒有攝影技術，會書畫的藝術家又少；影像留不住，只好用石柱代表，一來它不會壞，再者它也是我們文化的一部分。