An attempt at a summary for you to perhaps aid understanding:
It sounds to me, given you mentioned that you haven't read the anus material or philosophy or any of that, that you've developed a certain picture of what anus is about. I can only presume it's been informed by the postings you've read on these metal forums and perhaps by the various bits of propaganda produced by the staff.
I think that the propaganda and some of the posts shouldn't be taken in any kind of absolute or even literal manner. There's usually alot of sarcasm in the posts, for example. Maybe it really is Born For Banning's position, but an arbitrary standard like "kill everyone below IQ120" is (hopefully) obviously foolish. Rather, what I get out of the post is that it is showing that we do not value intelligence, that people of low intelligence often don't realize they're stupid, and that maybe if they did realize it, they wouldn't go beyond their means and might try to do the best with what they've got, or something like that.
You then came back and responded in a harsh absolute way. Ex: degrading people because they eat fast food is an insane judgment. This is misunderstanding the point. The goal is not to create a standard of absolute evil upon which if you eat a cheeseburger you're the fucking devil. The fact that someone ate a big mac one time, or even a few times, says very little about them. What might say more is if they are a regular customer. What would say even more is if they're a regular customer and they're overweight. The more qualities and patterns that reveal themselves, the more they begin to paint a picture of what a person values and cares about.
The current day and age is insane in alot of ways in terms of what it values and cares about. We have alot of very easy ways to accomplish alot of things in our lives. There's easy entertainment with television, easy food with fast food, and all the other examples that get thrown around on these boards that you no doubt are aware of. These things come at a price. They show that we are willing to raise up ease at the cost of other things. It is these things that we try to investigate. We want to know what we're losing by leading these modern lives because we are undoubtedly losing something.
The diagnosis often runs like this: We are losing meaning to our existence when we throw off challenge and all that comes with it. We no longer have great health, let alone flourishing. We simply keep society going for the sake of keeping society going with no greater goals or ideals to help us recognize that maybe some things shouldn't be kept around. This situation bothers alot of people and that's why many of us are here.