Also, drug buyers are customers. It would seem crazy for a dealer to endanger customers on a regular basis. So, buying drugs in a shady part of town should be (relatively) safer than most activities?
I don't know about being relatively safer, if you have a higher income than average you definitely can become a target because, via their other business (extortion, kidnapping and asking for rescue) they can also obtain profit, so being successful can be risky.
Now, are dealers purposively endangering their clients? I don't think so, but risks do come with getting drugs (e.g the police/military comes by, a rival cartel comes by, etc). Also, most of their income comes from the drugs they sell in the states so I don't think losing customers here is such a (monetary) loss to them.
You (wrongly) assume drug dealers and their surrounding cast are balanced and rational individuals. There's a huge spread, but when you interact with criminals living on the edge of society you should not expect to be safe.
And, thus, targets of every group opposed to the particular one with which they are attempting to do business.
> It would seem crazy for a dealer to endanger customers on a regular basis.
Of course, dealers don't want to target their own customers.
Every other network's customers, well, that's just part of targeting the competition's business more generally.