There is no doubt that YouTube has a massive monopoly over how content is consumed around the world. And given the audience you can reach, it is no wonder that content makers in New Zealand are increasingly looking to YouTube as a means of reaching their audience.
When you use the YouTube site, whether as a content-creator or a content-viewer, you must agree to the Terms of Service. These terms act as a contract between you and YouTube. For content creators, the crucial part of this contract is that, when you upload your content to YouTube, you are giving YouTube:
a worldwide, non-exclusive, royalty-free, sub-licensable and transferable license to use, reproduce, distribute, prepare derivative works of, display, publish, adapt, make available online or electronically transmit, and perform the content in connection with the service and YouTube's (and its successors and affiliates) business, including without limitation for promoting and redistributing part or all of the service in any media formations and through any media channels.
In other words, you are giving YouTube a broad licence to freely use your content for any purpose. Something to bear in mind when you next publish your content on YouTube.