What about cherry-picking modules, briefly going through their source code (and, hopefully, test suite), then manually (read: copy/paste) importing them into th

What about cherry-picking modules, briefly going through their source code (and, hopefully, test suite), then manually (read: copy/paste) importing them into the project at hand? What are the ethical implications of this, though? Is it different than importing the module directly via package managers, license file and all?