As a kid, I hated table manners. They were an imposition on my ability to eat (and talk) at the dinner table, and they constantly undercut what I was trying to focus on, which was either to a) shove food in my face, or b) pontificate loudly on which dinosaur was best.
Manners were rules that were forced on me by fusty churchgoing ladies, and fell into the same anti-kid category as things like turtlenecks, "quiet time" and couches that weren't to be jumped on.
So when I was old enough, I learned enough basic manners to not be disgusting to girls, but I more or less shunned any and all ideas of etiquette for the entirety of my 20s. I did not know at the time that this would basically turn my social life into an anxiety-ridden nightmare.
Every traveler knows that manners change from culture to culture – the differences between cultures are often the source of our best stories – but that manners themselves are ubiquitous. The reason for this isn't because human beings just like making dumb rules about things, but because we realized early on that social anxiety is a nightmare, and that having a standardized set of social rules that everyone follows helps allay that anxiety.
Different cultures have different standard ways of greeting each other, for instance. Handshakes were originally a way to show the person you were greeting that you were unarmed, or, in the case of cheek-kissing cultures, were displays of genuine affection. In places like Japan, the depth of a bow shows the depth of your respect. And more complicated (or "secret") handshakes were a way of showing belonging to a specific group.
But in America, we lack a single unified greeting. (Go in for a hug when someone else is going for a shake, and you will spend approximately the next 10 months sporadically remembering the moment and restraining yourself from walking into oncoming traffic. The other person in that encounter may remember you, despite an entire night of otherwise delightful interactions, to be "that dude who decided to try and get way too intimate with me"). You could make the argument that it is for this reason, at least as much as social media, that we've all become shut-ins who would rather spend time with our screens than with other people.
How coffee changed the course of civilization
How coffee changed the course of civilization
Table manners serve a similar purpose to standardized greeting rituals – they allow you legitimate avenues to non-verbally express your enjoyment of a meal, for example. They also offer you specific rules to violate if you wish to be deliberately rude. The point isn't to make rudeness impossible, it's just to make it obviously intentional or unintentional. Without manners, fights can start and grudges can be held over mere miscommunications. With manners, they are probably only going to start over legitimate grievances.
But the table manners we have now have ceased to be useful. The no-elbows-on-the-table rule was initiated in medieval times because tables were much more crowded, so putting your elbows on the table was a contemporary equivalent to manspreading. The pull-out-the-chair-for-the-ladies rule, while always chivalrous, was initiated not because women were helpless, but because their dresses were huge and they couldn't gracefully do so themselves. And the "clink" we do with our glasses when we toast is a descendant from when we used to allow our guests to pour small amounts of their drink into ours to show that we had not poisoned them.
So most modern table manners are just cultural vestigial limbs. They have ceased to be useful ways of easing social anxiety. But we have not necessarily adapted with new manners that serve our times. For example, there's no subtle manner in which a vegetarian, a pescatarian or a vegan can indicate to the chef their dietary requirements while at the table. As a result, it's always a loud refusal followed by an explanation, which is why half of non-vegans are always saying "Ugh, vegans can never stop talking about being vegan."
Well, yeah. You keep trying to serve them non-vegan food. The same problem arises for people with intolerances, allergies, or, in the case of alcohol, previous problems with addiction.
Likewise, modern tables could adopt smartphone baskets to keep guests from checking their mail while at the table. They could involve pre-meal email notifications that Aunt Susan has strong opinions about Colin Kaepernick, or that Cousin Amy just discovered the "truth" about chemtrails, and that neither topic should be broached if we want to have a meal that doesn't devolve into shouting matches. They could incorporate different colored plates that diners could choose to indicate to all present how willing they are to discuss their romantic lives – green for Steve, who's so totally in love, red for Tiffany, who will bring someone home when she's damned good and ready.
It's a common theme in internet memes to say, "LOL I'm so awkward at parties. I'd rather hang out with cats." And while, yeah, fair enough if you're a cat fan, it's worth noting that our ancestors figured out a solution to social awkwardness literally millennia ago. The solution is table manners.