EBS volumes are expensive due to their durability features, which provide value through detachability and resizing, but at a cost of $0.08/GiB or $0.24/GiB when considering replication. The high cost is because EBS was designed for traditional datacenter environments, not cloud-native ones. Object storage like S3 in AWS can be 24 times cheaper, making it more cost-effective for large data volumes. Shedding local disks entirely may be necessary for optimal economics in the cloud, but "tiered storage" approaches often lead to operational headaches and are an architectural dead-end.