"Drug crime and other crime go hand in hand." [Citation Needed]
"Those who are currently dealing drugs don't know how to play this game and will lose." And then get a real job.
"They can't go and get a straight job because they have no provable work history, probably a criminal record and few contacts outside of the "underworld". They also have become accustomed to a lifestyle of nice cars and (possibly multiple) high maintenance girlfriends, so McDonalds isn't going to cut it." You have no idea what you're talking about. The margins are not that high.
Your image of drug dealers applies to an extremely small minority. You must only know what these people are like from TV.
You claimed that drug dealing is a non violent activity. I showed an example of where that is demonstrably not the case. Roughly 65% of the coke in the US comes through mexico where it is causing serious violence.
In my home country (UK) we also have problems with violence and intimidation from drug gangs in many deprived areas.
If you run "the happy weed co", violent uneducated thugs are the last people you want doing your customer service.
If this were the case , former drug dealers would be being offered jobs as pharma reps.
Which, incidentally, doesn't stop at the lower-level employees but goes the whole way to the top, and is one reason it is quite likely that the "newly legal mary jane barons" won't be the same as the pre-legalization illegal barons, they'll be existing ag/pharma megacorps, who are set up to do what a legal business in the field will need to do (including already being plugged in with the applicable regulatory bodies.)
Violence may not be required however in cases where everyone is already scared witless of them. Drug crime and other crime go hand in hand.
If you legalize drugs completely , then serious businesses run by people with MBAs , Venture capital, marketing teams, legal departments etc come into the game. Rather than street level violence, battles are not fought in patent courts and with government lobbying.
Those who are currently dealing drugs don't know how to play this game and will lose.
They can't go and get a straight job because they have no provable work history, probably a criminal record and few contacts outside of the "underworld". They also have become accustomed to a lifestyle of nice cars and (possibly multiple) high maintenance girlfriends, so McDonalds isn't going to cut it.
So they will look for other lucrative opportunities where the MBAs don't want to compete with them (because it is illegal).