system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: how does tread (like snow tires and boots) provide better grip if they are packed with snow?
gpt
It isn’t just tread on snow tires that makes them better for snow than other tires. 

Most rubber gets hard in cold/icy conditions, so the rubber isn’t able to grip and is as good as having tires made of rock. However the rubber compound used to make snow tires is made in a way that keeps them from getting as “hard” at cold temperatures, allowing them to remain more grippy in those conditions.