Why Aren't 'Super Tickets' More Popular?

With the annual box office revenues and physical media sales dropping, some theaters are coming up with ways to entice audience members.

Engadget relays the marketing of a theater in the UK where a patron purchasing a ticket for Kidnapping Freddy Heineken is given a voucher for a digital download of the film at a later date.

Why is this not thing? The article states some 'SuperTickets' exist in the US but I can't say I've seen or heard of one. But it makes sense to bring viewers into a more expensive theater viewing with the lure of a free one once available.

Now, this of course wouldn't work for all movies. Everyone in America has purchased a ticket to The Avengers by this point but many indie or low-budget films that would struggle otherwise not only get more revenue from the theatrical proceeds but more exposure. It sounds like a win-win as opposed to someone randomly catching the film on Netflix a few years later.