> Maybe what you describe happens with automated/integrated tools, but I doubt it. The claim is not wrong, for flights. There are big systems (Amadeus, Sabre,

> Maybe what you describe happens with automated/integrated tools, but I doubt it. The claim is not wrong, for flights. There are big systems (Amadeus, Sabre, mostly) who manage flight-reservations for big airlines. But it's a bit expensive, and airlines usually also offer their own reservation-systems now. There are also lowcost airlines and charter flights which are normally not available through them. But probably 90% of commercial flights in the western world happen through those reservation-systems. And Hotels have a similar situation. You can theoretically book hotels, and even trips with train, ships, buses or cars through the centralized systems, but usually only the big companies are available through the reservation-systems. This has mostly historical reasons, but also because it's expensive, and is a bit complicated. This is why alternatives like booking.com emerged, who are cheaper, and could adapt faster to the changing market. Amadeus & Sabre are annoyingly old and "heavy" in how they operate. Though, this all is changing slowly. The travel-industry is trying to move to new APIs for handling modern demands of travelers. And The old gangsters have started to branch out to web-stack, with JSON and restful APIs, offer free documentation on Github and youtube, and even have discord now.