I teach 9 hours (actual classroom hours) a week. This is not unusual in higher ed, teaching loads are 4.5 to 12 hours depending on research expectations. For every hour in class I probably spend twice that time in preparation (writing lectures, setting homework assignments and tests) and in grading.
On top of that, committee work ("service" is what college profs call this). Committees can be time consuming. Committees do things like review colleagues for promotion and tenure (which can be a rough business), approve new courses or degree programs, and review applications for summer research money.
That brings up the remaining thing a faculty member must do, at least in many schools -- research. This is the most difficult thing most faculty have to do. You have to write papers and submit them to journals. The journals send these papers to other experts ("referees") who give thumbs up or thumbs down. (I've been a referee a few times myself.) If you don't publish so many papers, you don't get tenure.
There's an expression for this. Not one that I can directly use here without my post getting deleted. The abbreviation is FTS.
You have any idea idea how many hours I have spent working "on the job" when I was not physically in the office?
The answer to that is virtually all of them.
You guys cut a pretty fat hog. Where is the product?