Premine can work as long as the public has confidence in the distribution.
NEM for instance has 3000 stakeholders.  Taint analysis was used to remove hundreds of sockpuppets and the large scale diminishes any return from sockpuppets.

In contrast - you can have something like NxT (100% premine) which only had 73 stakeholders, of which 20 owned the majority, bought all the NxT for 21 BTC.  Probably most of these 20 big stakeholders were sockpuppets since there was no taint analysis used and it was such an obscure IPO that it was likely the same people signing up multiple stakes.