I've often thought the same thing.
Now at those hours, you can reasonably sleep and try to manage through it, but at some point, the lav tank will be full, there will be no place to use the bathroom, get even basic things like water, or food, and it becomes a threat to your safety and well-being to remain trapped on board.
At what point, in such a goat rope, do you think it would be fair to take matters into your own hands? What if you have children with you? Now you're risking a DCS "reckless endangerment" claim if you take them with you out the Emergency Exit, whether it was really an endangerment or not (I'm pretty d*mn sure as a pilot, I can determine whether an action on board an aircraft is safe or not, but now you're risking custody of your children as well).
I have no problem going to the lockup by myself for 6-12 hours (I'll make bail and head home), plea bargaining it down to a misdemeanor (pretty sure a jury would agree that 12+ hours locked against your will in an plane, especially an RJ that doesn't require air stairs (just taxi over to a terminal exit and walk them up the stairs into the terminal for cripe's sake) isn't necessary and is certainly avoidable), and suing the crap out of the airline that did it to me.
But throw some kinks into it and now you're in a different situation. Whatever happened to that "Passenger Bill of Rights" that guarantees they can't do this to you? Every airline should have a deplaning contingency plan using air stars and getting close to the terminal to keep people from being held prisoner like this. Simply unacceptable.