There appears to be no way round this other than to write the whole OAuth handler yourself (or get one elsewhere) - significant overkill for a development environment only 'issue'.
I have written the app to handle the getting of the google profile details as it starts and force an authenticate if they are not present.
This means that the login:required will work as expected in the production world and force you to authenticate to google before you even get to the application... then the app just gets the profile details because the tokens are already present.
login:required in the dev environment just puts up a screen which you just 'ok', then the app attempts to gets the profile details but forces the authentication itself because there are no authentication tokens present.
It's unfortunate, but it's a single step in a development that users will not have to use, but it works.