As thekaleb mentioned the creator seems to reference this symbol a lot in his games. Here is more of a back story (after some google-fu of course as I'm not very familiar with the games)
Seems like Keen 5 has it as an easter egg to reference Wolfenstein [1].
And Wolfenstein uses it since the game has a "Nazi Party" within it (if you fight them or fight with them I'm not aware of) [2].
Interesting quote from [2] "The inclusion of the swastika led to the banning of the conventional game in Germany, as cultural stigma against the swastika is high there."
Seems like Keen 5 has it as an easter egg to reference Wolfenstein [1].
And Wolfenstein uses it since the game has a "Nazi Party" within it (if you fight them or fight with them I'm not aware of) [2].
Interesting quote from [2] "The inclusion of the swastika led to the banning of the conventional game in Germany, as cultural stigma against the swastika is high there."
[1] http://www.shikadi.net/keenwiki/Keen_5_Easter_eggs#Swastika
[2] http://wolfenstein.wikia.com/wiki/Swastika