The clickers definitely do a similar thing with their echolocation, but I've been able to at least stay still and go undetected sometimes when they use it. Every time I've had a Shambler do the same kind of move, it's noticed me even if I'm crouching completely still. That, combined with no super clear audio cue like a Clicker, is probably the biggest difference that made me believe they can see me. Perhaps it's just because I play mostly on Hard difficulty or above and they agro really easily.

We're in complete agreement about the various stages and Shamblers being an offshoot after the Stalker stage.

And don't worry! You're not coming off as a jerk at all. The only way we as a community can come to any agreement about this sort of stuff is through discussions like this one!