I don’t know that it connotes the kill on sight taking precedence over other actions in general. But it does connote an extreme attitude that would virtually preclude any other action against a familiar. Extreme enough that it would have me second guessing other aspects of the campaign and have me reevaluating my willingness to participate in it.
And when that opportunity presented itself, the pixie took out the familiar as a priority. She killed it on sight. Is that not clear?
Would you "reevaluate your willingness to participate" in a game where the DM threatened your character's hit points? Or your ranger's beast companion? Or your summoned velociraptors? Or your necromancer's shambling undead? Or your metal armor or weapons with a black pudding or rust monster? How about your Strength score when faced with shadows? Those are just other resources, as is a familiar. As a DM, I'm taking aim at all of them. If the answer is "no," what is the meaningful difference to you between these things and a familiar?
If you are using "kill on sight" policies so that when the ranger and their hound walked into a bar without offering a direct threat half the bar patrons decided that that innocent and well trained wolf must die and drew steel where no fight was looked for and where it didn't make narrative sense then yes I would reevaluate my willingness to participate in the game.
"Take out a familiar given the opportunity" is very different from "kill on sight".
I don't understand why you kill them on sight. They are a resource, but not a particularly dangerous one. Why would an enemy kill the familiar on sight, but not kill the much more dangerous wizard or warlock on sight instead?
"Kill on sight given the opportunity" was what I said in my second post to which some people are objecting. What's curious to me is why is that a problem, considering all the other resources that the DM targets regularly, presumably without objection.
From the perspective of creating difficulty in a challenge, it's more likely that I can create ongoing tension by taking out a familiar - potentially creating a meaningful choice as to spending gold and time (both valuable resources in context) - and less likely that I can actually take down a PC, given a typical D&D 5e character's resilience. Your question seems centered on matters of realism ("Does it make sense to attack the familiar instead of its master?") which I find to be a secondary concern and one that is easily addressed given it's a game of make-believe. Need a reason? Make one up.
Because as a DM I don't "kill on sight given the opportunity" as a general rule for anything. My NPCs have different motivations, relationships, and threat assessments.
So do mine. So do many DMs' NPCs, I'd wager, so this isn't very unique in my experience. It's pretty easy to come up with those motivations, relationships, and threat assessments. Even on the fly when they've turned their sights on the familiar. I'm still not sure this gets to the heart of the objection though.
