Probably because the vast majority of the "programming" field as it stands today barely exercises computer science knowledge. Linked list optimizations, heaps, that stuff isn't even on the radar of most devs hacking on a startup, frankly, because the language hides it away. And they are not inferior programmers if they can execute on their knowledge, are they?

I hate that, to most folks who are into CS, CS is a yardstick for how much value a hacker will develop. "Can't optimize this from O(n^2) to O(n)? I have no idea how you keep your job." There is far more to the value produced by a hacker than the typical interview questions, and this elitist attitude out of most compsci folks is obnoxious.

This is why, even though I understand CS, grilling me on theoretical CS in your interview is automatic points off and I'll accept the position that actually quizzes on practical. I'm definitely of the mind now, being a self-taught programmer with a working knowledge of compsci, that I will learn things when they're needed to execute (not so they'll sit around in my brain waiting for the manager that Googled hard interview questions to ask).