depends on the type of milk. In Germany we have H-Milch, which has been heated to about 150°C for a few seconds and therefore been sterilized. It keeps several months unrefrigerated. Downside is it tastes like cooked milk and has some of it’s vitamins destroyed. If possible buy milk from the refrigerated section.

I find UHT milk is far more common in Poland too. In the UK it is less common.

Shelf stable milk. Super common across the continent.

Very different. The eggs are because the film covering natural eggs protects them. They legally can’t be cleaned (which also means the animals can’t be laying in shit, like American eggs). Kept at room temp to avoid condensation.

Milk is ultra pasteurized and sterilized to make it shelf stable.