As a college student I would actually say that this tool is pretty very useful for keeping up with the various things I purchase for myself, for others, and that others purchase for me (e.g. Chipotle, pizza, groceries, etc.). The minimalism & simplicity are a plus. Moreover, the functionality outlined by this statement is what I find to be truly useful:

"You can cut and paste the text from the results box into an email to all your buddies that owe you or you can save the worksheet...and send a link so they can see the worksheet that you created."

The fact that everything is coordinated by name also allows for a lot of flexibility. For example, if for some reason I wanted to add multiple rows, all with the same "Person", the system assumes that these people are the same based on the name, which is what I would personally expect.

Overall, kudos for a nice simple tool.