Nicotiana rustica is not the plant in a cigarette. It is a separate species, considerably higher in nicotine than the Nicotiana tabacum grown commercially, and the difference is large enough to change what the plant is used for. Where commercial tobacco is a mild stimulant taken habitually, mapacho is used in quantities and by routes that produce strong physical effects, including nausea and, at the upper end, states the practitioners are deliberately seeking.
The routes of administration are unusually varied. Johannes Wilbert's continental survey recorded it smoked, drunk as a juice, taken as snuff, licked as a syrup or a paste, and applied in other ways besides, with different peoples favouring different methods. Preparation differs accordingly: leaf cured and rolled for smoking, boiled down for a liquid, ground and mixed with ash for snuff.
The use that matters most for understanding it as a sacred object rather than as a plant is blowing. Smoke is blown deliberately over a person, over an object, into a space, along the length of a body, and this is done as an action with an intended effect rather than as an incidental part of smoking. It is the point at which tobacco stops being a substance a person consumes and becomes something a practitioner directs.