I think it is important to remember that this dealer did not receive his extended sentence for just 50 gms of coke, he did receive the extended sentence for repeated drug violations. It is also important to remember that most users, abusers, and even dealers do get light sentences for 1st time offenses. He may have spent little or even no time in county jail for that, may have gotten only a fine. 2nd time he probably got a stiffer sentence. So having been caught twice, sentenced twice, and serving his time twice, and knowing what a future conviction would do- he still went back to dealing. So no I don't feel real sorry for him.
Will taking one person off the street stop the drug trade? No. Is this the answer to stopping the drug trade? No. What will stop? I don't know. Maybe more preventative efforts. Maybe putting more effort in to first time offenders. More rehab, vocational efforts, counseling, better rehab programs and etc. Stronger 2nd offense penalties. More of an effort to keep them from the 3rd strike. But the fact is, there will always be those who will go for the third strike no matter what you do. Some people always seem driven to take it as far as they can go.
Comparing DUI's to drug dealers is like comparing apples and oranges in some ways. But in some ways it is the same. Repeat offenders often get off or get light sentences many times. They lose their license, they drive anyway. They continue to drive drunk. They just try to hide better. Just like 3rd strikers, they take it to the limits- until they kill someone or they get sent to prison (then they are back at it when they get out.) But it is important to understand- they are also addicts- just like the drug addicts. So maybe they need to do the same as with drug addicts.
Courts don't often order rehab- that is often considered a personal choice (besides if the court orders it they have to pay for all or some of it), and most rehabs are overbooked. Depending on the area, getting into a rehab can take a year or more. Some areas it isn't even available except as an outpatient.
LOL, Please don't get me started on child abusers and murderers.