There seem to be some common themes among the guns-and-ammo stockpilers. They are, unsurprisingly, the same themes that crop up before, during, and after every convulsive event—including many, many imaginary ones.
1) There are people who are stocking up on guns because the local grocery store is out of toilet paper, and they are afraid roving bands of diarrhetic hooligans will be coming to their house to procure their toilet paper.
2) There are people who are stocking up on guns because the local grocery store is out of toilet paper, and they believe that owning a gun will allow them to more easily procure someone else's toilet paper.
3) There are people who are stocking up on guns because they believe restaurants being limited to takeout-only options will be so calamitous that all of society will crumble around us. It turns out that movie theaters, happy hours, and art museums were the only things left to hold this dismal nation together, and without those things they believe the thin veneer of propriety separating Americans from their bestial instincts will go up like flash paper.
4) There are people who are stocking up on guns because the first three groups are bloody insane and scaring the bejeebers out of them, so they figure they now need to arm themselves against groups (1), (2) and (3) rapidly going Mad Max the first moment their pre-apocalypse garage-based beer supply runs dry.
Even now, preparing for worst-case scenarios, there does not seem reason to believe toilet paper will be in short supply once the initial wave of panic-buying subsides. The same is true for most foods. The crops will continue to grow; most factories and other industries that produce essential goods, rather than nonessential ones, will have great financial reason to stay open and produce as much as can be produced, albeit with likely vastly improved health monitoring and (we can dream) government-mandated sick pay to encourage anyone with so much as a sniffle from steering clear.
People who expect America to turn feral are saying more about themselves than the rest of us. People forever thinking that this next thing will be the thing that turns all of government into a fiction are much like those believing every earthquake and storm as a sign that Jesus is coming to rescue them and leave the rest of you to rot in your shaking and/or soggy hell.
There are a great many things to worry about, mind you. How elections will be run; what new fascist shudders will shake through the Trump White House under the banner of a "national security" Dear Leader was wildly indifferent to, until it began to make him look like an incompetent oaf; how we can mitigate layoffs on a scale not seen since the Great Depression; the details of how to feed those people—and make no mistake, we will feed them, no matter what the most sociopathic lawmakers demand.
Roving bands of thugs coming for your toilet paper, probably not so much. Roving bands of thugs coming for your toilet paper in such numbers as to completely overwhelm your town's law enforcement officers, the National Guard and the U.S. Freaking Army If It Came To That, leaving only you, Biff GunGuy, to do the necessary murdering—no.
Note, all of you that are not in groups 1-4, that "gun stores are doing enormous business after an alarming event takes place" is itself nothing to be overly concerned about. This is what happens, every time. After every mass shooting, Americans of certain tastes flock to their city's gun stores to buy whatever weapon was last used to murder innocents—because they worry that specific gun will now be banned. During every hurricane, there are numerous grumps who scowl at local reporters and say “well there'd better not be any mischief around here because me and my nineteen guns and closet full of ammo know how to deal with mischief-makers.” This is part of the American psyche.
It means only that Americans are frightened, and have money to spend toward whatever industry can promise to alleviate that feeling. For some it is canned food. For some it is toilet paper. For some it is ... guns. Of course.
