AWS EC2 magically routes to S3 using private IP

I've deployed an EKS cluster, each of the EC2 instances has its own public ip and all attached to the same VPC.
The routing table for each of the EC2 instances subnets looks as follows:

Destination     | Target
----------------------------------------
192.168.0.0/16  | local
0.0.0.0/0       | igw-06d8c484aaba8d136

So if I understand correctly, every time I read from an S3 bucket (in the same region or not), it should be routed using the internet gateway to the internet, and if that's the case, I should see charges for it.

However, I don't see any charges for it, I tough that maybe AWS network magically taking care of these routings but they actually provide another solution and these rules aren't in any of the routing tables.

Not that I'm against free services, but I prefer to understand this before reading lots of data