1. They are easily misplaced.
"Where was our telephone book again?"

2. They are outdated.
"That's the old one—"

3. Google is faster.
Google Local can find almost anything.

4. They are impersonal.
What will you do to find reviews of businesses or driving directions to them? Google, of course. Why not start there in the first place?

5. They are expensive.
Ink, paper, plastic bags for protection, gas for delivery vehicles, salaries for employees, etc—

6. They are unwieldy.
Telephone books are large. So large, in fact, that it is frequently impractical to use them without setting them on a table.

Good uses for telephone books:

1. Projectiles
A telephone book thrown across a room can present some serious force.

2. Fuel
The pages can be used for starting fires, though it is best to avoid using printed paper for such purposes.

3. High Chairs
Telephone books aptly placed can transform regular chairs into seats appropriate for small children.