Daoism is controversial to me - the main concepts involve "going with the flow", and that you should act through inaction, essentially "just don't worry about doing anything, and everything will fall into place". Daoism has flexibility because of this though, and I took away from it that each individual can make of it what they will.
Confucianism seems to be more of a standard way of living than a personalized religion. In fact, Confucianism seems to not be really a religion at all, but more of a philosophical system. It has more domain in earth than in the heavens - the main concepts like ren and li are about respect to family.
Considering these, I can better understand the saying - confucianism is a standard for people, which people are expected to uphold in public, whereas in private life, people make of religion what they will, and choose their path, ending in death, which is basically the realm of buddhism.
