Your last sentence is a little confusing, if you're implying you could use your human capital and work, you're clearly going to be beholden to other people, and can't say fuck you to "any job, any time". In addition to that, we're back to the idea that 50k a year is fuck-you money, which it's not.
Long tangent incoming.
Fuck-you money is getting confused with a comfortable level of money. Most people will never ever get close to fuck-you money. Fuck-you money is black cards and reservations almost anywhere because you tip ludicrous amounts. It's being told the plane is full so you just upgrade to first class (if you weren't in there to begin with). It's being able to turn down any job because you could easily live at the same comfort level without it. It's only working because the work brings in stupid amounts more cash (that you probably can't figure out where to spend) or it offers you more than that (influence, stimulation). Just being able to say no to a job is not the same as that.