Kittel & Kroemer is the worst book on the subject I've ever seen. Reif is much better. Both are used to teach at the undergraduate level, so it may be that students don't see the difference as the Prof. will typically skip over the very detailed explanations given in Reif. Also, the last few chapters in Reif on non-equilibrium statistical mechanics are typically not covered at all in undergraduate courses.
I'd also like to point out that Leonard Susskind of stanford is teaching a course on statistical mechanics currently, and the videos should be on itunes in a few months. Scans of few pages of his lecture notes are available here: http://www.welkinsky.com/Statistical_Mechanics/Lecture_1.html