I would suspect that the common stock and preferred stock are priced according to their value (voting rights, preference at payout, etc). I think that ownership

I would suspect that the common stock and preferred stock are priced according to their value (voting rights, preference at payout, etc). I think that ownership of common stock by other investors with the desire to ensure that common stock gets fairly represented (i.e. gets its money's worth) in a liquidity event is the biggest benefit here because it may balance the desires on both sides of the fence.