Except for the assholes who lace their pot with LSD or something similar. Or do you not consider them to be pot users anymore?
NEVER encountered anything like that in all the years i smoked....most people i knew and bought from would not sell shit like that....if you go and buy from the lowlife on the corner you get what you get,including the shit that goes with it.....i knew who i was buying from,and i knew they knew their supplier.....your talking about the moron pot smokers Con....know your guys....there is the legit and the shady.....know who each are and you will have no problems....
Most of the really good "suppliers" that I've met have pretty much dabbled in only 1 thing......
Plants and fungi. Most of them don't want the added hassle of having a hard drug charge on them. Pot is a misdemeanor, meth/coke/heroin are all felonies.