At the beginning Taoism was not a religion at all. It was a philosophy. It eventually was mixed with traditional Chinese religion inorder to maintain the legitimacy of the Emporer when it was named the official religion of China. Previous to that it was viewed as a rebellious and seditious philosophical movement that threatened the 1st Dynasty's divine claim to power, and It's teachers were hunted and put to death.
Family's found sheltering Taoists as they traveled could lose their homes, lands, and lives for taking them in. It was the Tao's lack of heavens and hells, demons and spirits, eternal rewards or punishments that was so dangerous to the Empire, and it's inherently understandable logic that there were no spirits, gods, devils, demons, or angels just humans trying to live in harmony with the natural world they are surrounded by and at the mercy of. It spoke to the complexity of reality, of our world without requiring praying to this or that imaginary being for blessings or mercy, who the Emporer was the the supreme divinely appointed intermediary with on earth.