They're just like other default subreddits, which is to say that you can unsubscribe from them. I only resubscribed recently because I started working at reddit and figured I should know what's going on in my own company.
We use a review script that creates a temporary branch in github and sends an email to everyone you specify to review it. We then kill that branch when the review is over. Any time you push code, you run our test suite on your changes then create a review. Since these are encouraged to be small and behind config flags to not affect all our users immediately, it happens quite often. Once feedback is taken from the review you enter our push queue yourself and push it out yourself. If the code is possibly dangerous, we recommend those pushes wait from Friday night to Monday morning for safety's sake.
> Realistically, how many people repair Android or non-Apple phones? How many iPhone users would, when faced with a broken phone, try to fix it themselves rather than take it to the Apple store for repairs?
Not enough, and that's the problem. iFixit's purpose for existing is to get people repairing their things (electronic or otherwise); this is why we make guides and sell tools and parts, why we make all our guides freely available under a Creative Commons license, and why we spend a lot of time and effort convincing people that yes, they can repair things.
So when a corporation makes a visible effort to discourage these same people, we get frustrated. Yes, most Apple consumers don't want to repair their iDevices. But they never will if Apple continues discouraging them.