Comment by Sharlin

Yeah. The chocolate was of course a triviality, more important was the idea of encouraging people to give public thanks and the associated (extremely immaterial) karma points when thanks are due. In this culture (Finnish) we're perhaps not very good at giving praise, and even worse at receiving it, so it helps to have an established ritual for doing so. Also, I think at least one of the original goals was to mitigate the silo effect and encourage people to help their coworkers in other projects and such.