That's an excuse, it maybe sky-blue ,white ,black or anything else then why orange ?
and we can see amazon is also same why so? Do you know why it is so let see.
  

Warm Colors: Reds, oranges, and yellows. This is a bright, vibrant set that conveys energy and excitement.
Think of things that incorporate these colors such as sunshine, roses, sunflowers, bright sunsets, and fruit.