Maybe Jon was referring to his own experience, which is what I gathered from that segment of the podcast.
Alcohol is harder to quit than weed, for many reasons. The only two drugs I've ever done were weed and alcohol, and weed was, by far, the easiest to quit.
Some people use weed as a crutch to help deal with stress, much like alcohol, but alcohol is usually easier to get, especially when there's a store on every corner selling it to any who are old enough to buy it.
Weed is one of those "drugs" one can indulge in from time to time, without needing more, or having an adverse effect on the body, when compared to alcohol. I smoked from a pipe, normally, so when I stopped smoking, I also stopped coughing up little black loogies in the morning, during my breathing exercises.
As an asthmatic, I was still able to smoke weed, however. Mostly stopped, because I didn't want a piss test to stand between me, and any job I want. Plus I save a few hundred a month, now.
Alcohol is addictive, will make you black out, become violent, destructive, and will wreck your body. Weed, not so much. It only makes you lazy and unmotivated, if you're a loser. Plus withdrawals are minimal, if not zero.
Weed is so innocuous, yet so potent compared to alcohol, that I hope to see in my lifetime weed not only be legalized, but for it to be taken off of the Schedule 1 drug list, and made relatively illegal to drug test for.
Truly legalizing weed would cut severely into the alcohol and pharmaceutical conglomerates, as well as the Prison-Industrial complex. We can't have that now, can we?...