DRM is to prevent content being available outside of the official/legal channels in the first place. This is clearly not working, as pretty much everything that's available legally with DRM is also available illegally without it.

The majority of users would not be capable of getting the URL of the actual movie out of the HTML source, saving it to disk and sharing it with friends.

The majority of users is, however, capable of going to thepiratebay and downloading the same movie through bittorrent.

It takes one 'internet dork who frequents HN and reddit' to circumvent the DRM and upload it somewhere where the average user can easily get to it.