My understanding was ease of delivery and route. Everywhere listed is either in a major metro area, or on an interstate that connects major metro areas (and refineries). BCS, while we do have hwy 6, isn't really "near" a major metro area, and we aren't on an interstate, and we aren't really close to refineries (but close enough that a driver basically can't go many other places without maxing out there drive hours or having to find a pipeline fill Station to refill their tanker (or head back to houston)
The shortage of CDL drivers (and especially those with hazmat endorsement) also doesn't help.
The shortage of CDL drivers (and especially those with hazmat endorsement) also doesn't help.