Drugs in Brazoria County.
I think it's best to consider the area as a whole rather than in terms of separate district communities.
I would imagine that drug usage in Brazoria County is equal to (and due to availability, perhaps higher than) what occurs in counties elsewhere in the US of similar size and proximity to a metropolitan area.
If it exists, it's probably available in Brazoria County.
Drug trafficking in Brazoria County is somewhat unique in comparison to most of the US, but not at all unique (as far as I know) within the Coastal Plains region.
Brazoria County was added to the Houston High Intensity Drug Trafficking Area (HIDTA) in 2014.
https://www.federalregister.gov/articles/2014/10/10/2014-24176/notice-of-hidta-designations
The greater Houston area is a major distribution center for the transshipment of illegal drugs to other parts of the US. It may be the largest single distribution center in terms of volume.
Additionally, Brazoria County lies within a transit route from the border to the Houston area.
The main corridor (I-69/US 59) does not go through Brazoria County, but transporters wishing to avoid the scrutiny on the primary route could travel through Brazoria County into the greater Houston metro area.
IMO, the odds of Jubal Alexander being in the "wrong place at the wrong time" with regard to drug trafficking are higher than in Des Moines, Iowa or even Atlanta, Georgia. (Not picking on Atlanta -- it is also a major distribution center.)
It's within a reasonable possibility that he selected a spot to sleep where he could have witnessed drug trafficking, whether it be a simple local drug deal or something involved in broader distribution. MOO.
The spot is somewhat secluded in that one would have to be fairly close to see anything or anyone under the overpass.
It also seems possible that with his regular presence in that spot that he could have been mistaken for undercover law enforcement if that location was used for any drug trafficking.
I can't rule out the possibility that drug trafficking could have a role in his death. He would not have to be an active participant for that to be true.