from Why are some people allowed to keep their rewards, but others not?
Can you actually become a whale by posting? Fat chance.
So essentially, you can't be a whale from posting because you have to work a regular job. All the mega whales got that way through early mining when no one was around. So you work, then post, and then if you get successful you can keep your rewards. But I posted for 6 months and just reached 100,000 SP (without a job, posting 3-4 times a day). If you want to be a real whale of 1,000,000+ SP, well that's 5 years of posting 3-4 posts each day. Some people got that just by "ninja mining" for STEEM early on. Others joined early and got into the tens and hundreds of thousands just by posting. Did anyone flag them for making rewards, even if they had no job?