This was bound to happen. You have piracy and online sales, a scarce amount of people visit video stores anymore.
Piracy is not a major cause of the industry's downturns. As a matter of fact, record labels and entertainment companies have earned increasing billions as time goes by.
The main factor is the change in the times. Going to a store that might even have a limited stock is no longer such an enticing idea, considering that over half of the world's music is available to anyone with a PC and the know-how.
A similar case is the shift from horse carriages to automobiles. Even if you raised the finest horses and built the sturdiest carriages, your business would still go down due to the change of the times.