[skybrian]

Not that this is a good idea, but how do you suppose a window manager could be modified so that it's not useful for "bad" purposes?

It seems difficult to do for general-purpose software.

[3np]

I'm saying you could forbid it in the license. Like some licenses might allow personal but not non-commercial use, you could come up with other disallowed uses. Seems like a better idea than attempting to limits its use to your in-group.