Your post reads as an uncharitable brag about how you're better than me, even though you conclude by agreeing with me.
It's not my duty to go above and beyond for people who are trying to abuse and take advantage of economic needs to treat me as a work animal, not a person in hopes they learn a lesson. You can if you want to, but I think that attitude is what enables that behavior, not mine.
It's not going to work all the time. Some people are jerks and there is no way to convince them to work together with other people. They just take everything they can and give nothing back. My experience is that these people are pretty rare, though. The vast majority of people who act like jerks do it because they are convinced that there is no other option. I'm not saying that you are being a jerk, but the attitude that you espouse just reinforces their view. They believe that they must take everything, or there will be nothing left for them. They believe that they can't give anything back because it will all be taken from them.
Give something back for free, even if they give nothing back. How much you give is still under your control. It won't always improve the situation, but my experience has been that it will sometimes improve the situation.
You're also taking a single action to generalize to all my behavior -- for example, you're ignoring the possibility that I would both "forget" the out of hours idea, but present them with studies about how treating "knowledge workers" better leads to increased output or other similar "during work" activities that might influence their behavior.
You're also ignoring a slew of other concerns, ranging from my emotional health to my willingness to lock IP up with someone I perceive to be a negative actor in society.
All because you want to brag about how you're better than me and be "right".
Instead, I recommend showing the advantages of flexibility. "I worked overtime to give you this thing which would not have been possible under your rules, how about cutting me some slack as a reward?" Somebody has to budge first. Now, if they are only interested in sucking up as much of your time as possible and paying you as little as possible -- then they are being abusive. As in any abusive relationship, your top priority should be to get the heck out of there. As a fall back position, of course, you should protect yourself as much as possible, but having an a priori position of being just as petty as your boss will really only result in unhappiness for everyone.