I imagine that game's designers drinking beer while watching a sci-fi movie marathon.

The name refers to the length of viewing, rather than the film medium; therefore a movie marathon can consist of television episodes too.

Popcorn is considered a staple for movie marathons.

So do all of these additions make a movie marathon?

It had been Nathaniel's idea that we could have a movie marathon of old monster flicks.

Except even if Michael was back home, it's not like he'd necessarily come crawling through her window for a movie marathon.

A model wandered over and said, "I want to see 12 movies this weekend, go on a movie marathon."

Thus the casual viewer got the flavor of the old movie marathons in smaller portions.

As a result, the movie marathon was cancelled.

Tarantino has been known to invite Doom over to his home for movie marathons.