Call it the spaghetti incident: A brawl that erupted between two women on the New York subway after one slurped her pasta from a take-out container is once again raising questions about elusive transit etiquette.
"What kind of animals eat on the train?" asks an offended woman sitting across the aisle from the spaghetti lover.
The dining lady responds with a barb about the other's weight, and it goes from there. When a male passenger tries to break up the fight, he gets his face clawed.
So is it rude to eat on public transit? NY Daily News commenters seem to be having a heated debate on this one.
"If you are like a child and have zero willpower and must eat on the train, have some courtesy and eat a cold sandwich, at least it won't stink up the place," writes one.
"Spaghetti is not a snack. That people are rushed and pressed for time and need to eat on the go is pure NY BS," adds another.
"That lady should have minded her own business!" counters a third. "If u don't like what u see in a car ur riding in get up and move to another car."
And on it goes: Are there unspoken rush hour rules? Is food that requires utensils over the line?
In any case, it looks like artist Jason Shelowitz, who tried to elevate NYC subway riders with official-looking etiquette posters, has failed.
The yellow posters warned passengers against 10 common transgressions, including eating "smelly" food and littering, as well as treating your fellow morning commuters to the Beyoncé track blaring from your iPod buds. The cardinal transit sin, though, is trimming your nails. (Please don't ever.)
At the behest of transit officials, the posters were eventually removed. Pity.
Over in Washington and Hong Kong, officials have banned food and drinks on their subway systems - to help stamp out rats.
In Beijing and Shanghai, food bans and the accompanying fines are being met with fierce opposition from riders, many of whom like to spend their long commutes noshing.
What about you? Do you like to indulge in a fragrant Big Mac on public transit? Or, do you feel like tussling every time the high-school crowd boards your train, stinky salt and vinegar chips in hand?