When POW initially started the allocation was POW lite - not even ERC20 so listing was not possible.   Allocation of POW was and is done by linking up your social media accounts.   I suspect that anyone who did not receive anything tried to link an account that had been created less than a year ago.

Now they have created a bridge whereby you exchange POW lite for the ERC 20 equivalent 

Not a scam that's for sure.