What is the main use of pipes in the context of cannabis?

Pipes are primarily used in the context of cannabis for smoking. They serve as devices designed specifically for the combustion and inhalation of cannabis, allowing users to smoke the plant material efficiently. When a user packs cannabis into a pipe and ignites it, smoke is created and can be inhaled directly through the mouthpiece. The design of pipes facilitates an easy and convenient way to consume cannabis, making them a popular choice among users.

The other options, while related to cannabis, do not accurately capture the primary function of pipes. They may reference different methods of consumption or preparation, such as rolling joints or concealing cannabis, but the essence of what pipes are used for is specifically tied to smoking.