How to add city geolocation atomatically? (without any extra clicks from the user)

Hi there,
I would like to use this module to implement some localization of my comments.

Use case: The user completes the comment form to post some comment, and after completing the form shows his or her city/state/country besides his or her name.

Now I can see that using the "Geolocation Google Maps" option, the user has to click the "My Location" button and even in that case the browser actually asks the user if he or she allows to get their location.
And even if the user accepts, Google gets very close, I mean, it tells you even the street house, and that´s too much for me.
But even in that case the user can always choose to type in whatever information he wants (and that could be very far from where he actually is).

If I decide to use "Geolocation HTML5" mode, it´s easier, but even in that case, the user needs to check the geolocation checkbox and allow the module to get his or her location.

Is there any way to get that automatically in an anonymous way, and without extra steps for the user? For usability reasons it would be better if you don´t force the user to do any extra clicks...

Any insight on this will be very much appreciated, thanks!

Rosamunda