As an artist, just to share my experience: when you need photos, videos, music, anything for your project, you don’t have to pay for that. You can use Public Domain marked artistic materials for free, without any obligations. It means the person who owns copyright is either dead, either alive
but devoted it to Public Domain, so these pieces are free of copyright. Companies and individuals devote their artistic works to Public Domain because they want public to use it and/or because it’s good for promotion. It works like advertising, exactly like giving away samples of products and trials. It’s a fantastic promotion strategy – to use Public Domain materials for your projects and give away your own pieces with links/credits to your site/shop or anything you want to promote. And, as an example, here is one of my royalty free, public domain photos anyone can
use the way they like, including commercially for profit, which means that if someone make hundreds of dollars on this photo I will not ask for profit share etc.. This photo was taken by my family member, no photographers involved. CopyRight free. Super!