You're missing the point. If you make four separte purchases, you're paying the tax on four different items. If, for example, you only buy the DVD, you are completely unaffected by any taxes from the book/ticket sales and DVD rentals. Because the taxes do not affect each other at all, it not any of the upstream componetns of the final product (many of which are shared, including the work of your authorship) that are taxed, but only the final products sold.
If their were zero tax on anything, the authors income would be much higher. His income is based on a function of the total economic bottom line. He is in essense being charged the full tax on every individual sale and because there are multiple sales its taxed multiple times.
I have some questions about the paper in our book. The lumber company purchases trees and harvests them for its use to produce products and uses some of the byproduct to heat his factory. Is that taxable ? The lumber company then creates wood products which includes paper and it sells the paper to the printer. The printer uses the paper to create adverstisments to promote its own company as well as for internal office supplies and prints the books for the distributor. Is that taxable ? The printer sells the printed material to the distributor who gives complimentary copies to his best customers and friends for their personal use. Is that taxable ? The distributor sells to the book stores and the book stores sells to the customer. I assume thats taxable. Then the customer sells the book on e-bay. Is that taxable ? What if a relative of the distributor who was given a number of free copies sold books on e-bay ? Is that taxable ? The second person to buy the book, reads it and sends it to recyle plant. The recycle plant makes newspaper and sells the paper to the NYT's. When the NYT's sells the newpaper, is that taxable ?
Final question about procedure. Each step along the way, taxes might be due from folks who are not ordinarily considered retailers. Tell me again how the IRS would not be needed ?