That 14 day ( or 7 day) US rule is long gone.
I think what you mean to say is it's still there, but no one pays attention to it.
Although, it must have had some effect somewhere down the line. My biggest customers pay in 14 days all on their own.
Nostalgia Time:
Remember back in the old days when you would drop a load at the food terminal then go upstairs and collect your pay ... in cash !!!
Back then there were poor truck drivers all over the place. Tax returns showed they could only feed their poor families once or twice a month, and they all shared the same pair of shoes ... but every one of them drove a brand new pick up truck and had a Mercedes in the garage ... LOL