There's a completely irrational knee-jerk reaction to curl|sh. Do you trust the source or not? People who gripe about this will think nothing of downloading a tarball and running "make install", or downloading an executable and installing it in /usr/local/bin.
I will happily copy-paste this from any source I trust, for the same reason I'll happily install their software any other way.
It really depends on the use case. A one-off install on a laptop that I don't use for anything that gets close to production - fine by me.
For anything that I want to depend on, I prefer stronger auditability to ease of install. I get it, theoretically you can do the exact same thing with curl/sh as with git download/inspecting dependencies, installing the source and so on. But in reality, I'm lazy (and per another thread, a 70s hippie) and would like to nix any temptation to cut corners in the bud.