I think I get where you're going with this, in that, the burden to run this and review the source is too high, that it almost seems like a waste of time. If that is your point, then I agree with you.

I don't know much about docker, but doing a "curl | sh" peeks my interest, then downloading additional binaries into /usr/local/bin, I'd want to take a closer look. Obviously, this is a case by case review, till it sits well with me. If I was going to run this in production, I'd want to have a really good idea of what this was doing and what to expect, so I'd probably take a closer look at the source if it was not clear from the documentation.