Once upon a time it seemed like technology was easier to keep up with, but by now we can never get enough new releases to be satisfied. Even if you just bought a new phone, chances are that the manufacturer has already announced the new version that will be coming out in the future. While realistically virtually nobody really needs to upgrade to the latest model, that does not stop people from wanting to do it. Instead of simply buying the new phone and then wasting all of the money you spend on the old one, sell old mobile phones and recover some of the money that you originally invested into them.
Whether it is a matter of staying stylish and cool or there is some new feature, the bottom line is that new phones have great appeal to people who can afford them. However, not everyone is so picky so there is still a market for slightly older phones. Obviously condition and functionality have an impact on the overall price, but the bottom line is that you can get money for your older devices. There is no catch or scam going on here, it is a simple process that helps you get a little extra cash.
Even if you do not think the deal is amazing by any means, the money you get will be pure profit compared to just leaving it in a drawer somewhere to rot. Even recycling old phones can be a pain, so there is no quick and easy way to get rid of them even without looking to gain anything in the process. There is really no logical reason to argue against selling an old phone that is not being used, as it will help someone else out, be good for the environment, and give you some money.