Monero also has on demand transparency via view key
Did you just waste thread space?
This is only for incoming txs. You cant see any spendings using viewkey.
It seems they are working on making it possible.
From :
https://github.com/monero-project/bitmonero/commit/ebf97d76f0020eb027175818ebbdafd6d578aa77wallet: new {ex,im}port_key_images commands and RPC calls
They are used to export a signed set of key images from a wallet
with a private spend key, so an auditor with the matching view key
may see which of those are spent, and which are not.