Some countries have trendy ccTLDs, and startups buy in to their domain space. Vox Media has more details:

Even very small countries get ccTLDs. Here’s a close-up of the area around Australia and the many small island nations that have their own domain names. Some of these countries realized that they could make a lot of money if they opened their domains to foreigners. The result: popular websites like last.fm (.fm is the domain of the Federated States of Micronesia) and twitch.tv (.tv is the domain for the island nation of Tuvalu). The .io domain, assigned to the British Indian Ocean Territory, has become popular among programmers. They associate the domain with the technical term input/output and use it to create “artisinal websites.”