I have spoken with several people recently who have visited China within the last year. One of the common threads they have shared is the propensity of the Chinese to spit, not just in public, but even in private spaces! We Americans sometimes spit too, but I gathered from talking with these recent visitors that the Chinese spit much more often and with less inhibition. You can see further confirmation of this custom while watching the US-China Institute videos, one of which shows Deng Xiaoping, the leader of China, spitting into a spittoon during a meeting with US officials.