It is the reason why playwrights would never distribute full scripts. You would only get your lines and the line before your line. You also wouldn't get a lot of time to study your lines. It was common for someone off stage with the only full script to help actors remember their lines.

This is a brilliant factoid

Emphasis on "in some cases, these unauthorized copies are the only record of a given play". This already happened with radio/television, and will happen with all sort of digital media as future historians scramble to study the late 20th century and early 21st century's internet culture.

Piracy is timeless.

*discreetly

You'd probably have to go a couple-few times to get all the words. A ticket sold is a ticket sold.