It was free some time ago.

Oh, this reminds me. Have to make two more!

So slow

People can't search...

I guess it's still the aftermath of the free The Ship key giveaway 2 months ago, where thousands of keys have been given away for free.

When activated on your steam account, each key would add the game to your library and spawn 2 tradeable "The Ship 2 Pack" in your inventory.

When activating a "The Ship 2 Pack" it would add the game to the library and spawn 1 tradeable "The Ship Complete"

TL;DR: massive key giveaway, 1 key gave 5 copies.

AFAIK, the devs have announced on their "The Ship 2 kickstarter page" that The Shipp will become F2P once the successor is finished (this might have changed and I'm too lazy to google for their kickstarter page).