Basically CS is a huge field and any assumption you make about someones skills just because they have a "CS degree" is almost certainly false to a greater or lesser degree.
Knowing everything about painting doesn't make you a good painter :).
Then again no one automatically expects an art history major to know how to paint (even though there no doubt is quite a bit of overlap).
I don't think I could write a simple echo clone in C anymore.
I miss C, but since entering the "real world" I haven't written a line of C for work purposes.
We definitely do C programming at my program (shell, malloc implementation, thread pool, web server, MIPS assembler/interpreter etc.). I go to Virginia Tech, a public university.