A disassembler could be made to ignore the upper 3 bits of all addressing (the 2600 does anyway). Setting the origin as $Dxxx or $Fxxx is really only useful to get the absolute addressed stuff labelled by the disassembly process.
I'm glad you noticed that. You actually hit the nail right on the head. Using the reset vector doesn't work a lot of the time.
Although it's true that data tables, etc...could be repurposing the upper 3 bits of vectors they hold for other uses The labels themselves missing this reference is of little consequence, IMO.