It's crazy it is resold but we don't even get it for our own use. Budgeting with credit card statements would instantly become so much more useful with less effort.

It does, at least in some cases. When I book flights directly from an airline, the bank knows the name of the passenger, the date of the flight, the origin and destination airports, as well as the cabin class. For one bank (Chase), the information is printed on the statements; for another they have a web lookup tool.