I think nowadays that games attributes are all over the place, it's more reasonable to use a fuzzy logic approach for categorizing genres. I can't speak for cookie cutter molds, but since the definitions of things are almost solely based on their acceptance of the mass at the time, here're my 2 cents of what personally comes to mind when I think of RPGs:
-Having maps/settings that you can actually walk around in, as opposed to static images
-Has more dialogues than most if not all other genres
To me, the label of "adventure game" seems to immediately spawn the profile of Myst and Tomb Raider. So personally, I tend to categorize games that're dialogue/story-heavy in walkable map settings without battles as more of a "non-battle RPG" than "adventure game", despite missing one of the typical elements.
I think everyone's core definition of the genres is just highly affected by their personal experiences such as the first game they played of that genre, what they liked about it, etc. So when it gets into that mixed-up fuzzy logic scenario, people have different top priority attributes when trying to weight them to be placed in a recognizable yes/no basket.
here as well.