Redshift table occupies exponentially more disk space in production cluster
Found this in AWS documentation, which describes this behavior clearly.

The default amount of disk storage space allocated to two tables residing on different clusters can vary significantly, even when the tables are created using identical data definition language (DDL) statements and contain the same number of rows.

Because the block size in RedShift is 1MB, all columns will take up 1MB per column at a minimum. On top of this if the DISTSTYLE is EVEN it will be closer to one block per slice in the database. Since there is no way to tweak the block size in RedShift there is no way to reduce the size of an empty table since the table's size follows below formula:


For tables created using the KEY or EVEN distribution style:


Minimum Table Size = block_size (1MB) * (number_of_user_columns + 3 system columns) * number_of_populated_slices * number_of_table_segments.


For tables created using the ALL distribution style:


Minimum Table Size = block_size (1MB) * (number_of_user_columns + 3 system columns) * number_of_cluster_nodes * number_of_table_segments

https://aws.amazon.com/premiumsupport/knowledge-center/redshift-cluster-storage-space/