You said "everything you need". I need shelter, I need food and water, but I want powerful computing, fast internet, a phone with cell service, treats and snacks and etc. I want games to play with my friends, I want gifts to buy for my friends. I don't need those things, but they greatly contribute to my quality of life.
Also:
> What does it even mean to question whether you can afford something you already get unlimited amounts of for free?
If I had unlimited money, my limiting resources would quickly become time and energy instead. So affording something would mean fitting it into my day/week/month/etc, and finding the energy for it. I have severe ADHD and executive dysfunction, so I don't always have the capacity for things I should be able to do.