You have had an enjoyable dinner with friends at one of your favorite BYOB restaurants.  You have brought a bottle of one of your favorite wines, and there is still some wine left when the dinner is over.  Rather than overdoing, or leaving the wine, you re-cork the bottle, put the re-corked bottle in a bag, and take it home with you . What happens next determines if you are breaking the law or not. If you put the wine on the floor in front of the empty  back seat row, that is an open container violation, even if you are not consuming the wine on the way home. You can be an asolutley responsible drinker, but it  is  still a violation.

On the other hand, if you put the wine in the trunk, or if there is no trunk on the floor BEHIND the last row of seats, then there is no violation:   that is what I advise you to do.