It's easy to grow compared with cocaine. You can grow the plant in a tent or if need be just on your windowsill, pluck and trim it, dry it, then smoke it or bake it in an edible. And even a single plant is good for quite a number of joints. Hash oil extraction is more difficult but most stoners prefer to smoke pure or tobacco mix weed anyway.

Cocaine in contrast, you need 300-ish grams of leaves to make 1 gram of cocaine, and a ton of chemistry afterwards to extract and purify it.