The advent of advanced computerized reservations systems in the late 1970s, most notably Sabre, allowed airlines to easily perform cost-benefit analyses on different pricing structures, leading to almost perfect price discrimination in some cases (that is, filling each seat on an aircraft at the highest price that can be charged without driving the consumer elsewhere).
It’s best to visit Greek islands within the same group. For example, I wouldn’t recommend visiting Corfu and Santorini on the same trip as they’re on opposite sides of the country. Instead, visit islands in the same island group: the Cyclades, the Sporades, the Dodecanese, the Ionian, the Saronic, and the Northeastern Aegean. For one, they’re close to each other. And two, they have frequent ferry connections with each other. For first time visitors to Greece, the Cyclades make the most natural and convenient introduction.
In recognition of the essential national economic role of a healthy aviation system, Congress authorized partial compensation of up to $5 billion in cash subject to review by the U.S. Department of Transportation and up to $10 billion in loan guarantees subject to review by a newly created Air Transportation Stabilization Board (ATSB). The applications to DOT for reimbursements were subjected to rigorous multi-year reviews not only by DOT program personnel but also by the Government Accountability Office and the DOT Inspector General.