At the risk of sounding glib, I don't think that's how most drug dealers in prison began dealing drugs. I could be way off, but the scenario he posits, wherein all hits mates are buying weed and he arbitrages, is probably not how most drug dealers come into operation, and certainly not how I suspect the prison-time crowd got into it.
It doesn't sound far off to me. My understanding is many start dealing to help support their habit and it grows from there. I don't have firsthand experience but I've had "friends in low places" so to speak. What do you propose as a more logical explanation and what is your theory based on? Thanks.
In urban environments, drug dealers are more plentiful, work on slimmer margins and operate in a riskier environment. In more cases than not, the drug dealers that are dealing with enough volume to catch prison time are those attached to gangs, or out of necessity to stay above the poverty line.
The picture painted in the article, at least to me, is perhaps the most likely way for middle class white kids to end up in prison for drug dealing, but most drug sentences serious enough to involve prisons don't go to middle class white kids, they go to urban blacks.
This isn't to say that the numbers are right, or fair, or necessarily representative of how the real world works -- but if we're talking about people in prison, this is more likely.
Most of what I said speaks in anecdotal language, but here are some numbers to back me up: http://www.jrsa.org/ibrrc/using-data/data_quality/data_eleme...