The thread title is how do plants make cocaine. I would guess it is very similiar to how people do;
Round up the tribal/group elder. Cut off his head in front of the tribe. Rape his wife. Threaten the rest of the tribe to cooperate or die. Enslave the tribe and force them to harvest the leaves and process the cocaine.
A bit insensitive??!1 This is what happens all the time. My dear friend is a Marine agent working with the DEA/CIA drug interdiction groups in Central and South America and he tells me that this scenario plays out on a very routine basis. You don't think those people enjoy walking through all of the carcinogenic solvents now do you.