What did you expect GET requests to be counted as then? As an aside, I think it's fairly well documented: https://cloud.google.com/storage/pricing#operations-pricing (lists "GET Object" under class B) [but disclosure: I work for Google]
That + it being more expensive than cloudfront and s3 came as a rude shock :(
In general I find google cloud documentation and the service much better and more pleasant to work with than AWS but in this case it is not. Both S3 and Cloudfront have much clearer pricing (and positioning). In network pricing, both S3 & Cloudfront are significantly cheaper