Why do people read papers at academic conferences?

I mean literally read them when giving a “talk.” This practice gives unfortunate credence to Alfred North Whitehead’s remark that the university has been obsolete since the invention of the printing press. Hearing someone read a paper is a far less efficient communication process than just reading it yourself. (This is especially aggravating when the paper has been distributed beforehand).

I’ve heard the practice defended by people who point out that not everyone is a good extemporaneous speaker, which is true, but it makes me wonder what such people do in their classes. How are they adding value exactly? Of course some people are skilled at mixing reading from a prepared text with apt interpolations, expansions, digressions, etc., which is a different thing. But too often in recent years especially I’ve run into the faithful oral transmission of written text (often accompanied by the dreaded Powerpoint “enhancement” of key paragraphs).