Yes, it looks like it was me who was confused. I did not know that github does not accept anymore the password when using git, and you're right that this is unnecessary. Sorry that I was rude, me implying that you were confused really wasn't a friendly thing.
If you use git often, and this is in the way for you, I think it's possible to save it in the gitconfig, tough, if that's fine. I think git should be able to use the credential manager of mac's too if you use that, but maybe it needs a separate package installed for that to work.