> Well my time is definitely not free; people pay lots of money for access to it.

Your working time is worth money, but your free time is free. Your time is only worth money (opportunity cost) if you'd otherwise be working on some money-making opportunity.

If it's 1. Hiring someone for $25/hr to mow the lawn while I work on a contract that's making me $200/hr, I'd choose to hire the gardener. If it's 2. Hiring someone to mow the lawn while I play video games, I'm better off if I mow it myself.