It's just you.

Looking at Amazon's m4 instances vs Google's standard instances.

   n1-standard-2=$0.1930  db.m4.large=$0.175
   n1-standard-4=$0.3860  db.m4.xlarge=$0.35
   n1-standard-8=$0.7720  db.m4.2xlarge=$0.70
   n1-standard-16=$1.5445 db.m4.4xlarge=$1.401

That's without Google's sustained use discount, so it comes out as cheaper most of the time.

Not for me! They are pretty much comparable. Google's sustained use discounts mean no lock-in, lower price and flexibility too! Considering the fact that Google Cloud's disks are way faster than AWS's disks, your overall price is much lower with Google Cloud.