Debian Games = OpenContent ?

[Christian Melsbach]

Hello and happy new year to all Debian-Games Maintainers!

I am trying to build a website about games that are open source and use open content. 
As far as I remember Debian has a very strict policy not only on the source code but also on the content of their software (graphics, documentation etc.). So does this mean all Debian games are "open content games" too ( http://packages.debian.org/unstable/games/ ) ?

E.g. AFAIK Flight of the Amazon Queen is only freeware (no open content) but is also listed ( http://packages.debian.org/unstable/games/flight-of-the-amazon-queen ).
So what does the term "non-free" exactly mean?

cheers
Christian aka MilesTeg