Perhaps the better question is: why not? The costs of not doing it are significant, and the sole “advantage” of not doing it is saving about 10 minutes per week.
Let’s start with food waste.
First, it is a huge problem that is steadily gaining attention. Roughly 30-40% of all food produced for human consumption is wasted, the majority of which takes place in households.
It is the single largest source of municipal waste in the US, making up 24% of the national stream. Worst, over 55% of US food waste is landfilled.
What’s the problem with Landfills?
Landfilled food has to be transported there, which represents roughly 65 million tons hauled and uncounted vehicle miles traveled every year.
Decomposition in a landfill generates between 15 - 30 times the amount of greenhouse gas emissions than composting because of their structure and chemistry.
Decomposition is much slower and can even stop altogether. Mined landfill samples have uncovered foods as much as 50 years old with no signs of decay.
Landfilling is a linear process that delivers minerals and nutrition from soil to a sealed chamber with toxins, which is both unsustainable and irresponsible.
Keeping food out of landfills and into compost costs less financially, costs less in planetary resources, increases planetary stability, and takes about 10 minutes per week.
Composting is arguably the lowest effort, highest impact change you can make to genuinely reduce some of the worst impacts of modern living.