A minor quibble (with apologies). If the GM in your second case, here (the fire beetles as a random encounter) wrote up that table, then it seems reasonable to say they think the fire beetles belong in that place. That doesn't necessarily imply eagerness, I agree, but there is some decision and/or authorship there.If the GM narrates mountains with giant nests in them, it's obvious that the GM is interested in giant birds of prey. That's the whole point of the soft move!
The contrast with (say) AD&D played using wandering monster tables is obvious: when I roll fire beetles as a wandering monster, no one thinks that I as GM am especially excited by fire beetles. It's just what I happened to roll!
Similarly, your first example--narrating the giant nests into a mountain scene--might imply a sense that giant eagles belong in fantasy mountains, more than an active interest in having the PCs encounter them--though again, there is an authorship-type decision happening, here.
I dunno why I'm quibbling--I don't really disagree with you.