system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why aren't football coaches expected to wear suits like other professional sport coaches?

I've been noticing that NFL coaches don't dress up in suits like NHL or NBA coaches, for example, do. Why? Just because? It's cold in a hockey rink and they still get all fancy. So.
gpt
The NFL currently has endorsement deals with either Reebok (up to 2012) and currently Nike. This covers all team uniforms, workout attire and sideline attire.

You're not allowed to wear anything that isn't by Reebok/Nike.

edit: bok not bock.

I bet Tom Landry's fedora is spinning in his grave.