If you accidentally send crypto to an exchange without a proper message/memo connecting the transaction with your account on the exchange, most exchanges will (for some reasonable fee) help you credit this crypto to your account or send the crypto back to the sender's address. Not Spectrocoin - they simply keep your crypto claiming there's nothing they can do and that your crypto is lost forever. I cannot find any other expression than just "thieves". Keeping money which was not intended for them is nothing but a theft.