Many drivers who face traffic violations while out of state think that they will not face any real consequences, so long as they refrain from driving in that state in the future.
But this is not the case; while it is true that another state does not have the authority to suspend a license issued by a different state, the state can and likely will share the details of your DUI (or other offense) with your state via the Interstate Driver License Compact, in which nearly all states participate. Per the compact, states share information with one another when traffic offenses are committed involving drivers from other states.
When a state that is part of the compact receives information on one of its residents about a DUI crime that has been committed in a different state, the home state will typically treat the offense as though it occurred within the home state.
As such, if you are charged and convicted with a DUI in South Carolina but live in North Carolina, South Carolina will likely share this information with North Carolina, and North Carolina may sanction your license under the rules in North Carolina.