Why do we store the issue data in s3

Why do we store our issue data as JSON in S3?

What are the pros/cons of storing this kind of data in S3 over our own sql database?
e.g.
- is it faster to load data
- is it cheaper
- does it take up less space as a json file on S3 than as a string in postgres. If so could storing the data as a binary help? (see quotes below)

quotes from https://github.com/dwyl/phoenix-ecto-encryption-example
> The reason we are creating the encrypted/hashed fields as :binary is that the data stored in them will be encrypted and :binary is the most efficient Ecto/SQL data type for storing encrypted data; storing it as a String would take up more bytes for the same data. i.e. wasteful without any benefit to security or performance.

> The best data type for storing encrypted data is :binary (it uses half the "space" of a :string for the same ciphertext)