Texas didn't have an open container law until September, 2001. Let that sink in.
According to a D Magazine article
from 1985, the only real deterrents were thanks to the work of Mothers Against Drunk Driving (MADD.) That same year a law was passed changing the legal drinking age in Texas from 19 to 21. The year before, a law went into effect hiking the fines for a DWI conviction.
Thankfully someone interviewed these lovely Texans
during the time these laws were being passed, and got their honest to god opinions on the matter. They did not disappoint.