I noticed your description of "drip" as an alternative fuel in your novel "Survivors". Many years ago I was on a task force in Farmington, New Mexico to catch and convict "drip thieves". I was then a Special Texas Ranger and worked along with New Mexico Highway Patrol, local law enforcement officials and the then Tenneco Oil Company Security investigators. Theft of drip was very big then, as probably now due to the high cost of gasoline. I will share with you some of what we learned from the experts, the actual thieves we caught.
First of all it is not called "drip oil", but only "drip" in thieves term. It is actually what the oil industry calls "condensate" and as you correctly stated is a by product of natural gas production. It is the condensate liquid that forms from natural gas as it is produced from the wells. Some wells are "wetter" than others and produce more condensate. Those are the wells drip users look for.