Like lawns. We seriously use way too much water, chemicals, energy and time on a plant crop that is basically only for our visual enjoyment. We often think of the big fixes, which are needed, where there are some low hanging fruit we could pick first that would make an impact.

https://news.climate.columbia.edu/2010/06/04/the-problem-of-...

https://blogs.scientificamerican.com/anthropology-in-practic...