If a friend bought me popcorn every week for multiple weeks and never says anything about debt, and then suddenly three months later says I owe them $50 plus compounding intrest, do I legally have to pay him back? At the same time, my friend actually bought popcorn for my coworkers as well (implying a gift as he did with me) yet he has apparently counted how much money the gifts costed and is talking about requesting payment, when none of us actually agreed that he was not buying us popcorn, he was actually loaning us money in the form of said popcorn, and expected payment (he never mentioned any of this of course)