Bookstores usually have coffee shops and chairs for customers to read. It isn't copying it if you read it. It also isn't distributing it. The bookstore probably has a license for allowing customers to read the material or some sort of rights.
I know Barnes & Noble and Amazon will allow you to read the first 10 pages of a book for free if you sign-in, have an account with them.
Personally, I think YouTube is the best advertising music has had since the radio. I often buy songs after hearing them for the first time on there. The links to purchase are usually right under the video or in it.