Don't be surprised, and don't feel bad. There is innumerable open source software we all depend on everyday without thinking about it. Consider zlib, libpng, libjpeg(-turbo), bash, bsd or gnu core utilities, random stuff ... and then the stuff you might sometimes think about, like openssl ...
That's maybe the biggest practical benefit of open source software. You don't have to keep track of who you owe what. A lot of these projects have had a few different critical creators and maintainers over the past decade or so. And we don't have to keep track of any of that. That's a huge efficiency boost.
(You should not re-distribute open-source software in a way that violates the license, but that's a separate issue from using it, and it scales a lot easier - everyone receives/uses many more different software works than they distribute.)
That's maybe the biggest practical benefit of open source software. You don't have to keep track of who you owe what. A lot of these projects have had a few different critical creators and maintainers over the past decade or so. And we don't have to keep track of any of that. That's a huge efficiency boost.
(You should not re-distribute open-source software in a way that violates the license, but that's a separate issue from using it, and it scales a lot easier - everyone receives/uses many more different software works than they distribute.)