In which I succumb to pop culture

Veronica Mars is my new favorite show. It gets bonus points for making it seem unnecessary for me to ever watch Twin Peaks. Miss Mars, however, sometimes makes inexplicable and repeated mistakes. Why send out dozens of *somethings* to a variety of addresses, hoping that one will make its way to the sought individual, and not have some manner of tracking which *something* is being replied to? And couldn't a blood test performed within 24 hours detect the presence of rohypnol?