After performing a refresh to a non-production environment, the blob storage for that target environment becomes redundant in reference to the old data. I think having a function to clean it up and coping the blob data over makes sense. It means that the blob storage in the target environment doesn't grow out of control, and that the data in it is relevant to the data in the database. In particular, I'm referring to documents that users may have attached to customers/products/vendors/POD/etc. I think building a process to copy them across to the target environment makes good sense.

* There is no way to clean up the blob in the target (unless it's a Tier 1 environment). The target blob files will essentially all be orphaned, with no way to clean them up and keep docuvalue and the blob (for azure storage documents) in sync. This means that the blob storage will constantly grow with the use of a sandbox environment and now way to ever manage it effectively
* If a customer wanted to do training on existing production like data, there is no way to do this when working with docuvalue documents. The training would have to consist of creating new documents, which increases the time in setting up the training been less efficient.
* If blob storage movement was an option, then the number of potential uses for making use of this increases greatly.