the prohibitions imposed by copyright also apply equally to all licensees, non-licensees, and co-licensors.
and what's more, the gpl, being a copyright license (rather than a licensing agreements), only grants permissions. it doesn't prohibit you from doing anything whatsoever. it's copyright that does. the gpl only grants you narrow exceptions, that enable you to control your computing, and to do whatever you wish with the software, without granting you power to go beyond your own freedom as to violate others' freedoms.
why do you seem to find that objectionable? why do you seem to resent not being granted power to abuse others?