As a socially awkward dude who has been in that situation before, I think the guys who describe themselves as friend-zoned are unfairly demonized. These guys generally aren't entitled and indignant, they're misinformed. When you grow up as a social outcast, you don't have the social experiences that other kids have. Your first kiss may come years after that of your peers. While other people are being invited to parties and learning how to interact with each other from an early age, these people are often excluded. If they're not learning how romantic relationships work from personal experience, then how are they learning it?
From entertainment. If your basis for understanding relationships is movies and TV shows, then yeah, it makes perfect sense that they would believe what they do about relationships. There's no shortage of movies and TV shows that teach young men that if they act like prince charming and stay by a girl's side, that eventually she will see them for who they are and fall for them. This is a notion that's hammered in over and over and over again, and then when people understandably believe that's how it works, they're treated like misogynistic deviants.
The analogy about "kindness points and sex" is echoed frequently, but I've never seen a situation where somebody who describes themselves as friend-zoned thinks that they deserve sex for their kindness. As far as I can tell, that's a mostly invented boogeyman that's used to demonize a segment of the population that's already socially at odds with the rest of them.
On the flip side, I have seen women who will exploit this sort of thing and use guys that put themselves in that situation for their personal gain. I've even had perfectly platonic friendships with female friends ended because THEY kept implying that I was in the friend-zone, even though I had zero romantic interest in them myself. Obviously that's not something that all or even most girls are doing, but I have seen it on multiple occasions, and that's certainly unfortunate.
Either way, my point is that these people should, if anything, be pitied, not demonized. They're not intending to treat women like property that they're owed for their kindness. They just legitimately don't know any better. And to any guy in that situation, understand that it is entirely a choice. Most people don't respond well to being put on a pedestal, and they respond less if you're all mopey that your affections aren't being returned, while making no vocal effort to communicate your feelings.