User blog comment:Vitios/Vitios, the Greedling/@comment-4.49.113.10-20130107225151/@comment-5663184-20130107230124

10% gold increase from the passive isn't all that much. You'd only be getting about 30 extra gold per champion kill, which is about as much as you'd get from killing a single minion. The W passive is a lot more, but it only takes effect upon champion kills. The Q damage increase has a cap, so it wouldn't get extremely high.