User blog comment:KaiserLos24/People Complaining About Champion VU's/@comment-4022742-20140521102159/@comment-8506165-20140521113059

As far as I know, it's not actually a cultural stigma. It's that the Ministry of Culture in China has already barred WoW from sale before until they "fleshed out" their skeletons and Riot are presumably hoping to avoid a similar issue here without having to sink resources into one Karthus VU with bone on display and one without.

(Chinese gamers themselves were reportedly annoyed at WoW's having to change the skeletons to pass the censors: http://www.china.org.cn/english/entertainment/216622.htm)