I am running nodes in a datacenter as well. Who is the SNO in your opinion? Me, the datacenter or both? 
When you say you’re running them: are you running them for yourself (you get the payouts)? Or are you running them for someone else who gets the payouts?
It sounds like you’re the SNO - but maybe you just provide managed-services for others: I dunno 
A defining quality of a SNO is that they complain on the forum. I have never seen a select node operator complaining on the forum, ergo, they do not exist.
If you own the datacenter and run nodes on spare capacity — you are operator.
If you are storj and running nodes on rented resources — then you are storj.
If you are nether — then you found a way to arbitrage compute resources. Don’t tell your provider. But it’s a very niche and non-scalable usecase and does not deserve a special naming.
They needs them to be filled, otherwise why to keep them?
Also not all customers have a prepaid contracts, so doesn’t make sense to keep HW empty.
exactly, otherwise doesn’t make sense to keep them. Of course may depend on a contract.
I heard that is quite expensive, so this feature is not implemented. As a customer you need to reupload your data and delete from the previous Regional/US Select placement.
they usually communicating directly because of the contract and agreed communication channels (please do not quote on me - I don’t have details).