I think egress costs are the primary factor behind "cloud bill shock". Tracking and understanding them is a key to avoid surprises when you get your monthly invoice from cloud provider.
This probably will depend on CDN. Google's CDN is part of the Load Balancer itself and therefore it won't affect geolocation. With "3rd party" CDNs it's different, of course.
Finally, the free version of MaxMind is great. Thanks for mentioning it.