It's also a strategic play: if you're dependent on imports for your food, some foreign power has a lot of leverage over you in a trade war or worse, an actual w

It's also a strategic play: if you're dependent on imports for your food, some foreign power has a lot of leverage over you in a trade war or worse, an actual war. So you spend money to keep production at home even though it might be more economically efficient to abandon those farms and import more of your food. Some of the EU's subsidies go to "agricultural peculiarities" or small producers of niche traditional foods. That's fine, you're still propping up demand for the raw materials - that milk is just as good as any other if it comes to a crisis.