Earlier quoted context omitted.
Your example is apples and oranges. Flock maintains private infrastructure that stores data. If the DSLR uploaded them to Rent-A-Center owned/leased servers it would in fact require Rent-A-Center to take the necessary steps. As Rent-A-Center would be the only group with proper access to data storage they would have inserted themselves into the chain of custody, and thereby have such obligation to ensure others data i…
AWS also maintains private infrastructure that stores data. Go write them asking to purge data pertaining to you from S3 and see how that goes.
If Flock was just an opaque cloud storage service for law enforcement to back up their mass surveillance to then sure, your argument would have merit; it's not, it's a giant database of photos, locations, times, license plate information, and likely a lot more. They're not selling cloud storage, they're selling (leasing?) surveillance devices and tools.