Is it a Chekov's gun or just a wall ornament?

I was recently thinking about when a detail is a Chekov's gun and when it's just, y'know, part of scene setting or world building. I was thinking this because my mind was pinging on things that I was sure were being placed in the story to be picked up later (the story was Mr. Penumbra's 24-Hour Bookstore, and the details in question *were* picked up again, but not in the way I expected), and yet not all details are there to be used later. To take an example that pops into my head, in Ann Leckie's Imperial Radch series, it's culturally significant that people in the Radch cover their hands and think uncovered hands are rude/indecent, and that fact is used to show differences in people's attitudes and statuses, but the fact of gloves and wearing them or not never gets used in a plot-defining moment. I don't know; maybe that's too general a plot detail to be a potential Chekov's gun. But even an actual gun on the wall might not be a Chekov's gun, it seems to me. It could be there just to establish the atmosphere of a hunting lodge, say. Or maybe it's a treasured memento of a grandfather who was a great hunter, and the storyteller is using it as a way to show how the protagonist feels about the grandfather, etc. etc.

Do you think you like it better if the Chekov's guns are unobtrusive and only reveal their Chekov-gunniness when they're picked up, or do you prefer to have an aura of menace around them from the start, so you wonder how and when they'll be picked up? Or does it depend? I was about to say that I think it shows more craft if you can't distinguish the Chekov's guns from the general scene setting until the moment comes, but now I'm not so sure.

flu immunizations

Look at this; two entries in one day--what is this, 2008? But it's because I had two very disparate thoughts that didn't sit nicely in the same post, so here you go.

When I did a unit on vaccines with my students, almost all of them were pro-vaccine ... with the exception of the flu vaccine. Many more people were on the fence about that or were actively opposed to it. The flu vaccine has the problem of being a best guess as opposed to a sure thing in terms of how relevant and effective it'll be against whatever strains of flu happen to go around, and I bet that contributes to people's feelings. With polio or measles or whooping cough, you're talking about just one illness, and the immunization is very effective; with the flu, you're talking about lots of different types of flu, and the vaccine may or may not be that effective.

Relatedly, we've been watching (against my mild objections; I guess I can tolerate the show) Arrow on Netflix, and in one episode, a drug dealer had a plan to create a citywide market of addicts by lacing a flu vaccine with the drug, so everyone who got a flu shot became addicted. "Thanks, show; great way to play to people's fears of the flu vaccine!" I shouted at the screen--and then started thinking about how this particular flavor of suspicion feels equivalent to the fears that people in Pakistan have with regard to the polio vaccine--that a purported good thing (immunization against a harmful illness) is being used by shady actors to accomplish a nefarious purpose.