Earlier quoted context omitted.
There's a rhetorical difference where "overbooking" puts the onus on the customer, and "oversales" puts it where it should be: on the airline who sold the extra tickets. And at any rate, the flight was not oversold anyway. It was merely the 4 extra United employees who put the plane over capacity.
How can "overbooking" possibly put the onus on the customer? Overbooking is entirely within the control of the airline, and the customer doesn't have the capacity to overbook, or even the knowledge as to whether overbooking could possibly occur. > And at any rate, the flight was not oversold anyway. It was merely the 4 extra United employees who put the plane over capacity. Well yes, that's the whole point of this di…
Oversales: The airline sold too many tickets
It's a thin distinction to be sure, but it reads with rhetorical significance to me.