Almond milk, oat milk, and other plant-based alternatives have grown fast in recent years. They give vegans and the lactose intolerant a dairy-free option, and they carry a lighter environmental load.
Lactose intolerance is a big part of it. Dairy milk causes bloating, gas, and other digestive trouble for many people. Alternatives made from nuts or grains avoid the problem.
The environmental case is the other driver. Dairy production needs large amounts of water, land, and feed, and contributes to emissions and deforestation. Plant-based milks need less of all of it.
Whether the reason is digestion, lifestyle, or footprint, plant-based milk is an easy switch worth considering.