Researchers did this experiment. One group of subjects got cake slices of varying sizes. The other group got cash. Everyone could see what others in their group (received). And those in the cash group who received less money than others were upset. But for the cake group, where the size of slices was harder to measure, everyone was (equally) happy. The study is in the Journal of Consumer Research.

In another trial, researchers found that subjects were unhappy when they missed out on a deal that had a specific quantity associated with it, like “buy one, get one free” versus a more vague deal that said, “get a larger bottle at the regular price.”

The researchers note that when you can't easily measure (something), you tend to be more focused on the experience that the good offers. They even say that we might be happier in a barter economy. Although it's easier to carry cash than a lot of trade-able goods.