Even if we presuppose that everyone working could choose not to work at all, I think your scenario is overly idealistic.

What your scenario changes is that the labor supply gets to be much more selective about the job they take. Supply and demand still exist. Moderating facebook is still a low skill desk job. The pay and benefit floor may be raised across the board, but I don't see what the market force would separate moderating facebook from the other jobs with comparable pay today.

Sure, you could quit a job moderating facebook and not have to worry about keeping yourself solvent. But the same goes for every other job. What would separate them from the jobs that they're on the same level with today?