The most popular papers such as laser jet paper for printers are produced en masse (in masses).
This makes manufacturing costs lower, resulting in a cheaper retail price.
Heavier papers
The heavier boards or papers that have an increased amount of secondary processes can result in higher costs, this is simply because of the specialist nature of these paper/boards.
Rolls of paper
Rolls of paper are made as continuous production.
Products like kitchen rolls, for instance, are seen in nearly every home.
The high demand has lead to further improvements of cost and manufacturing which is passed onto the consumer.
Books
Paperback and hardback books are different prices due to the density of hardback book covers.
Prototypes
One-off production or prototypes are often printed on high-quality laserjet printers.
This is slower but allows a design company to produce intended drafts of their graphics or prints.
