I just learned that Nmap is almost GPL except that they revoked the license specifically for SCO group for their SCO–Linux disputes.

This got me thinking, what do open source programmers think of evil companies or horrible people using their software?

Don’t get me wrong, FOSS software by its nature can’t be controlled or strictly prevented of being used. But in case of companies like SCO, that is a thing that at least can cause them headache and they risk getting into legal trouble. A programmer for example can modify GPL to make so that his software can’t be used by Microsoft or Facebook, but it is GPL for everybody else.