Valve contractually bounds UPS from releasing your package anywhere except the scheduled delivery address. Valve also paid for a service that works every 1-5 business days.
Saturday is not a business days. If you wanted it to arrive on Saturdays, a more expensive service and new contract should have been made.
Seeing as to how you spent $0 on shipping, I’m not exactly sure how you’re actually upset that you have to wait until Monday so you can play with a new toy.
This is a hard concept to grasp, but some people live closer to the manufacturing & main shipping facility than you.
If you were the literal first order, but you live in Alaska, everyone will get their order before you!
I’m using Alaska as an example don’t take it literal.