If someone starts a bounty and doesn't manually award it, the Community User should award 50% to the highest-voted answer.
However, that did not happen on this NetworkEngineering.SE question.
Interestingly enough, the same user started a bounty at roughly the same time on this Electronics.SE question, and Community User correctly awarded half the bounty.
Unless I'm mistaken, this is a bug... since we have a solid comparison from the same user on two different sites, on the surface I assume it's related to being in beta...