Of course that doesn't excuse people who do so in any way, they’re still the perpetrator. But I think your hunting rifle comparison isn’t very good.
Comparing it to a normal real world interaction where you expect people to just hang out and chat is ridiculous, if people just chatted it would be a totally failed set piece.
It's not an accident that she put a number of violent items out and had her assistants riling people up, something like "someone drank her blood" is exactly what it takes to make it into art history.
Does that not reveal the desires of the people who used the implements on her? (such as the one who cut her throat and drank her blood?). People could have chosen to not use the implements on her.
Maybe music doesn't count for some reason. How about something more interactive, like those "living history" reenactment villages (https://www.colonialwilliamsburg.org/). An actor comes up and challenges you to a duel. Do you accept and actually fight them? Someone on a soapbox in the town square is exhorting listeners to take up arms against the redcoats. As a matter of fact, you just toured an armory, and you see a patrol of British soldiers a few hundred feet away. Do you go arm yourself and attack the soldiers? Can you point to something concrete that differentiates these live interactive performers from Abramovic?
Is there any other piece of art where you'd take the content literally and attack the performer? Actually it's more than that, because if I took these instructions literally I still wouldn't attack her, since I don't desire to. You are making a leap that I still don't understand from "use as desired" to "well obviously anyone would desire to hurt her".
I can see why somebody might be uncomfortable with the general shape of argument from a "victim blaming" point of view. If you genuinely don't understand it then again, not trying to be a dick here but perhaps you don't understand subtext and intent in the way most people do.
The question I responded to is: "At least two thirds of the table is covered in various instruments of harm. What does that say to the viewer?" I maintain that "it says I'm supposed to hurt her" is not a rational answer. With the additional context that she usually hurts herself in these performances, it is understandable to have that thought, but not understandable or rational to act on it. I can think of lots of art that is intended to make you think about your capacity to hurt innocent people, but none that is intended to make you actually act on that.
Let me put it one other way: the commenter I initially replied to said that the presence of weapons on the table is useful context that should explain the actions of the audience members. I disagree, I don't think the presence of weapons is relevant at all or provides any amount of justification. I think the context you provided, that she usually hurts herself, is useful and does change my interpretation of her intent, but it still doesn't justify what anybody did. I still don't understand why somebody would choose to attack her. I also am a little bit skeptical that the audience would have been familiar with her other work. I'm not sure how the audience was chosen, but I don't believe the average person would have any idea who she was.
But this isn't just some mass-produced movie or family-friendly Broadway production. This is the cutting edge of art. It's supposed to challenge us. So perhaps we'll go beyond merely pretending at violence and do a tiny bit of actual violence. It's plausible, from a participant's perspective, that the creator of the piece intended that.
That's what I imagine the participants are thinking, anyways. They aren't just average folks of the street, after all, they're attendees at a crazy art exhibit. They've got to compete with people who hang themselves up by hooks driven through their skin, people who bite the heads of bats during rock concerts, and people who whip each other bloody in sadist orgies.
There's a whole world of consensual injury that to be honest I'm fairly personally prudish about, but nobody is making either of us participate in it. If people want to do it, if I'm honest I'm slightly judgmental but I feel like I should be less so.
Even without knowledge of her or her works, there's a lot of context that says "the risk is the point".
By putting harmful items out on the table, she made a deliberate choice for risk to be involved. The audience knows this. They know if she wanted a "safe" performance, she would have limited her selection. If the worst items were glue and feathers, the implied worse outcome is making her look like a chicken. Embarrassing, but not a huge harm. She put out a gun and a bullet. That implies (but does not outright verbatim say) that the sky is the limit - shooting me is an acceptable outcome.
That establishes the conceptual limit, but there are still societal shackles on behavior. Which is where "it's all about the risk" comes in. More risk = more sensational news, more notoriety for the artist. Clearly she wants something crazy to happen, else she would not put herself in a crazy position. So the audience starts pushing the limits of what is acceptable. I don't think they are harming her out of a direct desire to cause her harm, per se (might be some sadists in the audience), but there is an expectation that the risk level should ratchet up. But that ratchet doesn't occur without audience participation.
I think this perspective actually tempers the "this piece shows all humans are terrible sadists deep down" interpretation. Just like the Milgram experiments, it boils down to the general principle of humans tending to do the thing they think is expected of them.