Scurvey,
What if said No Name 737 was going up at > 3000 fpm? Perhaps s/he wanted to avoid the bunt as the automatics captured 8000 because if they left the call till passing 7000 there'd only be 20 seconds for onwards clearance to be issued (and of course some dill would be reading back his war and peace R/T) and by about 5 secs after reporting it'd be in capture mode.