[andOlga]

  git config --global core.hooksPath /dev/null

Then, in repos you want to turn it on:

  git config core.hooksPath "$PWD/.git/hooks"

This also works on Windows (and presumably other operating systems where /dev/null does not exist) as it seems to be handled as a special-case value.

[sph]

I would have liked for git to ask me first (like direnv does), rather than disabling them altogether, but this is good enough for now, so thanks.