One of the things that lends itself to abuse of things such as karma is a lack of cost. It costs nothing to vote something up or down, therefore we associate li

One of the things that lends itself to abuse of things such as karma is a lack of cost. It costs nothing to vote something up or down, therefore we associate little value with giving karma (as you're not losing anything), whereas the accumulation of karma typically requires some effort, so the cost of acquisition is higher.