The land-sparing/land-sharing (LS2) debate addresses ``food versus biodiversity'' trade-offs in cost-effectiveness terms, searching for land uses that minimize biodiversity loss for a given food production target. This paper argues that economic insights enrich this debate. In a theoretical model, I show that the introduction of some basic micro-economic considerations, i.e., profit-maximizing behaviour of land users combined with heterogeneous land quality, modifies or reinforces the recommendations of the ecological literature. I also argue that a broader welfarist approach would be more sensible than focusing only on Pareto-efficient outcomes in the food-biodiversity map as the LS2 debate has been framed to date.