If the happiness of the paying customer were the top priority of a university class, everyone in one should get a gold sticker and an A.

Alas, that sort of thing only happens in fairy tales and at Harvard.

In the past record store employees.

Also, to this day, some clothing store employees if you don't fit what they want as their 'look'.

But it is rare.

Some professors regarded their courses as being for weeding out people who would not become academics.

You could argue that in a sense the customer of a teaching institution is not a student, but a future employer who uses the diploma or grades as valuable information source.