I see exactly where you're coming from. The movie, in its barely hour-and-a-half length, is just a quick-fix -- it doesn't permit the sort of investment in the characters and plot that the hours and hours of gameplay it takes to finish FFVII do, and thus allows for the sort of passive people who would never dedicate all that time to become invested in the characters to try to claim they have a genuine knowledge of them when, really, they DON'T, because characters have either been reduced to pale shades of their true selves (such as Reno [and by extension Rude, too] being reduced to comic relief, or Aeris stuck with the whole Jesus-figure schtick and none of the personality that made her interesting) or given pretty much no screen time at all (poor Nanaki).

...Yeah, I can definitely understand why it's so incredibly frustrating that people are willing to stop there when they don't even know the HALF of it.