Food is perishable, and people like diversity in what they eat. Your example is an apples to oranges comparison. If he doesn't like what you offer, he'll go elsewhere.

> The difference with money seems rather to be that the value is created over time, where other transactions happen based on the current value of the things being exchanged.

Yes. Furthermore, when lending money to someone with interest, the lender gets what he put in and more, whereas say leasing a car out, he'll get it back, but it would have been consumed. This type of exchange doesn't happen with money.

> But given that we all die this doesn't strike me as morally wrong.

We can take that to it's conclusion and say nothing matters at all. People are out protesting against racial inequality, but we'll all die at the end, so it doesn't matter.