In many countries the caller pays for the cellular airtime. You have to know how much your call is going to cost before you dial it, so a new area code is neede

In many countries the caller pays for the cellular airtime. You have to know how much your call is going to cost before you dial it, so a new area code is needed. In the US, the cell phone user pays for the airtime even for calls they receive, so a new area code was never needed.