Information arbitrage , the average buyers isn ' t half as smart as you ' d give them credit for . Quite simply , not everyone knows how or wants to waste time getting a code . Some people might also think you need to pay an unlocking service for a code . Some people just search for GSM Unlocked , and buy whatever comes up . It adds value because now the phone can be used on any GSM carrier worldwide . Also , a good chunk of these phones are sent overseas . In some places cell phones are still quite expensive , Brazil for instance . Let ' s say say you speak another language . You relist one of these phones in your home country and use a courier service to get it there . The $ 10 phone gets flipped for $ 40 , then gets sent overseas for a final sale of maybe $ 80 . I had this happen to several Cricket phones I have sold .