When you are going to see "Dark"coin on a merchant, you can be sure that something illegal is behind and with the false centralized anon tech behind , its going to be a treasure for anti criminal organisation.
English lessons are in order:
Thesaurus Legend
Adj. 1. centralized - drawn toward a center or brought under the control of a central authority; "centralized control of emergency relief efforts"; "centralized government"
centralised
decentralised, decentralized - withdrawn from a center or place of concentration; especially having power or function dispersed from a central to local authorities; "a decentralized school administration"
Coins with a central mixer = centralized. Example Fedoracoin, XC in its first implementation, coins using an exchange for laundering etc. All of these examples use a centralized mixer or laundering service.
Coins where there can be a thousand nodes, setup by the very users of the network (all over the world) to process transactions are not "center". The function is distributed /
dispersed and is hence DEcentralized.
Centralized = the authorities can go to one place and shut the one and only central mixer down.
Decentralized = the authorities need to take down hundreds / thousands of nodes all over the globe.