Can you help me understand? Legit? Scam?

Hello.

Don’t really want to explain exactly what my interest in this is.

I’ve become aware of a business that is being run from someone’s apartment but I can’t understand it.

Basically one o person has 17 lines running from a home on 17 phones. Some mobiles, some landlines. People phone in on numbers which are alledgedly premium rate numbers from a well known telco.

Operators answer the lines, connect the caller with their friends or family back home in their own country, and they speak.

The operators get paid a basic and then extra if they connect for over 3000 minutes a day.

I’m struggling on this for several reasons.

1. how is the business operator making money?
2. if he’s running 17 lines from the same telco into the same property it surely can’t be illegal as it’s a bit obvious.
3. have you heard of this before?

Thanks in advance for any info.