"The key principle is that everything two entities - companies, people, Governemnts, whathaveyou - do together must be voluntary (they must both agree to it) and well-informed (they must know what they're agreeing to). So you can't coerce, and you can't deceive. The sole exception of self-defence and then all bets are off."
Which is usually never the case. Each side is usually trying to hide things from the other: either to outplay the other or as a defense against the other trying to backstab them. Confidence is something that usually only comes with trust, and trust is the exception, not the rule. Unless there's a crisis, one man usually doesn't trust the other and will tend to act in competition. That's why theoretical things like pure capitalism don't work in reality (asymmetry of knowledge) and why you have thought experiments like the Prisoner's Dilemma.
"In such situations then you are in fact being coerced, at one remove; all bets are off. You are free to act in whatever ways are necessary to ensure you are not coerced or deceived. Hack the meter."
Nope, because the electricity companies tend to have government mandate on their side. IOW, if all bets are off, what do you do when it's the OTHER side that has all the guns? Oh, and a willingness to use scorched earth tactics?