I do not know many people who have prepaid cell phones, but I understand a few of the reasons why prepaid phones might be the best option for some people. For instance, if a parent wants to get a younger child a cell phone, but fears that they will spend too much time on it, then prepaid phones are the way to go. Prepaid phones have limited minutes, so this will prevent the child from becoming too consumed in his/her phone. A prepaid phone is also beneficial to people who do not depend on their phones at all hours. Prepaid phones are also useful if one loses their regular cell phone, and needs a temporary replacement.
Although there are many legitimate reasons for prepaid cell phones, there are also some problems with this. Many criminals use it to avoid law enforcement agencies who cannot chase them. I feel that if there was a way to keep record of prepaid phone users, then we would not have this problem.
Overall I do not think that prepaid cell phones should be banned, but if they could be controlled by the law I feel that this would be less problematic.