Because most are "young-pass filters," and that makes itself obvious, as soon as I see them. I've learned that when I see a binary tree question, I might as well just wrap up the interview. They have no intention of hiring me.

I am mediocre at them. Most represent stuff I haven't done. A lot of it is common sense, but I'm solving them for the first time, so my approach is usually sub-optimal (I tend to start with naive approaches, then refine, if necessary). The testers are usually looking for a formulaic approach. A lot of my approaches are orthogonal to the "classics." I started as an EE, so I'm pretty good with things like drivers, SDKs and APIs, but they aren't really something that you can do in a 50-line test.

What's really insulting, is that when I'm asked, I usually send links to relevant gists or repos; often focused on the exact method that addresses the question asked.

It's ignored (so far, 100% of the time -the "faker" comment was made by someone that was explaining why they ignored it).