Why is denied?: Creative Commons ShareAlike

Hello,

I was reading this answer (last one) https://answers.unrealengine.com/questions/277405/general-public-license-gpl-or-free-software.html but still do not understand it.

Example: I will download object.fbx with CC SA license and use it into my game. I will package game and distribute it with object.uasset.

When someone wants object.uasset - he can. He can download my packaged game and copy and use object.uasset from it.

Ok, when you want to open object.uasset you need to use UE4 and agree with EULA. But CC SA does not demand that you need to have chance to open that format. It is same like when I will pack object.fbx into zip archive - still nobody have right to access source codes for zip archiver or right to even use zip unarchiver. Why is CC SA denied then?

This gets a bit complicated, but here’s my read on it. Under the CC-A-SA license, the same share-alike terms must be applied to your Adapted Material, which is material which is “based on” or “derived from” the original CC-A-SA material. So, if you include CC-A-SA content in your game, one could claim that your game is then based on or derived from, at least in part, that CC-A-SA content, and thus your game qualifies as Adapted Material so the share-alike terms must be applied to the whole game, including Epic’s Licensed Technology, which is prohibited by our EULA.