Knowing my friend, a fist to his face would have definitely increased the bill.

Since it would have been absurd to carry a crushed food box made for traveling in the hope that someone would very visibly re-crush it, the only thing the other passenger could have credibly questioned would have been the sunglasses. With those bent forward (front of each lens facing the other) at about a 40-degree angle, pretty much in the shape of an edge of the suitcase, and their case clearly stressed as well, the cause of the bending was obviously the other bag's pressure.

Still, the "invoice" was simply a request for compensation, and if anyone wanted to contest it, they could have flown, like my friend, back to Florida at a later date. That the female passenger didn't argue showed that she recognized her culpability.

For the record, I think simple assault pretty would pretty nearly disqualify anyone from challenging the bill, and that, if punches were an acceptable way to challenge the aggressive, the "Crushers" themselves might have been on the receiving end. Fortunately, that's not at all the case.