system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5:Why do we mostly consume chicken eggs, cow's milk, grape wine, and wheat bread?

Why not horse's milk, duck eggs, strawberry wine, and barley bread?  

Does it have to do with yield, or is it just Western tradition?
gpt
It's largely to do with yield, yes. Cows make a huge amount of milk (especially those bred to do so), a laying hen can lay about an egg a day, a grapevine is much more prolific than a strawberry plant. 

As for bread, wheat is high in gluten, which is important to getting that rise and texture. Even so, Ethiopians eat bread with a very different texture that's made from teff.