Because people wants duplication and imitation,only few people back then enjoyed what bitcoin have accomplihed and so they are creating a new coin with more features so people will adopt and use it and make a lot of money for the developer.
yes that is a fact and now it has become a profitable business, every one want to create their own currency they want people to invest their money in there and they can make good profit. while some forums and companies create their coins for offering their services, they start different services for the people in such coins through this way the coin become more successful.