Basically, "ticket paper" was like a blank check which you could fill in with a pencil saying "$10,000: first class ticket from NYC to LON", and the airline would accept that ticket, and reconcile it _back_ to the original issuing agent (who didn't issue the ticket, but instead had it stolen).
Once "the paper" was out there, it was prohibitively expensive to maintain and distribute a "rejection database" of serial numbers at all points-of-boarding, so tickets were accepted "at face value" rather than denying boarding.
As the world has become more connected and digitized, yes, airline use cases have always been one of the first to take advantage of integrating commerce and technology. SABRE is one of the oldest technology companies, and probably one of the oldest, most important "continual use" databases around. https://www.ibm.com/ibm/history/ibm100/us/en/icons/sabre/ ...great history in that article!
> The thieves are well organized, stealing thousands of blank tickets at a time, forging them and typically reselling them for $200 to $10,000 apiece, authorities said.
> “The airlines, in my humble opinion, could stop this,” said a Westlake Village travel agent who was recently held at gunpoint and tied up while thieves ransacked his business. Officials with the American Society of Travel Agents, which represents more than 11,000 agencies nationally, agree.
~1978: https://www.ojp.gov/ncjrs/virtual-library/abstracts/airline-...
~1999: https://www.latimes.com/archives/la-xpm-1999-aug-22-me-2752-...