Part of the premine has been given back to the community. To make up for the losses of early adopters, who would have lost their coins after the hardfork. (Proves enough if you want to)
Also keep in mind the fact that there has never been an ico or masternode sell of any kind. So the premine is the only way to gather development funds.
And yes, the developers hold a good amount for their selfs. But that's only natural if you ask me, wouldn't you?