Robert Stanek said:
Sharing a single copy of an ebook purchased with five friends is not expected and particularly when the five friends are all reading the work at the same time through a single shared account.
But that is typical reader behavior. If I read a good book in high school, that same paperback would make it through the hands of every one of the friends I hung out with in the upstairs cafeteria. I wasn't photocopying and reselling the text of the book, but I was definitely giving it legs.

Reading has always been a community activity in that respect.