well, there are many possible reasons ...
e.g., as a socializing activity (i.e., watch with friends); and some of them find "artsy" films too boring/slow/etc ...
e.g., sometimes, i need a break too ... ha ha ha
e.g., sometimes, i just want to know what the hype is all abt ...
e.g., sometimes, u want to know what the teens are watching ... so as to be connected with them ... hee hee