Nothing you don't know but...
It's only proprietary to protect the developers, and I'd consider that pretty reasonable. Game redistribution steals profits from the makers. My brother works at a company who has noticeable losses due to people torrenting their games.
And making them proprietary does nothing to prevent that.
Point being, they're not trying to wage a war against the freedom of information.
I didn't say they were. It's much more likely they simply don't understand the implications of withholding source code.
Creating games is a business, and without protecting their products/profits, those games were never be developed.
There are plenty of successful commercial open-source products, so please don't try to tell me that restricting one's patronage is the only way to make money from them.
I doubt anyone here would judge you for breaking your rule. Life is an exercise in exceptions, and to not recognize this sometimes can be a harmful oversimplification.
It's not only the ethics of software freedom that come into play here, but security considerations too. To ship a game as a statically linked binary, or with its own set of shared library files shipped with it, means that security holes in any library software used by the game will never get patched. (Note: I'm assuming this is how they distribute the game for Linux, due to the difficulty of ensuring compatibility with every distro when linking against system libraries.)
On the other hand, if these games were open-source, they could be packaged within each Linux distribution, depend on the system libraries, and any security problems would be resolved when those libraries are patched by the distribution.
This doesn't even get into security holes that may exist in the game itself, which are nearly impossible to audit, let alone fix, without corresponding source code.
I'm not entirely certain I want to compromise my computer's security by downloading these games.
Edit: In case further clarification was needed, I don't give a fuck if anyone here judges me for it. I am hesitant to purchase these games for my own personal reasons.