The most people (especialy wealthy people) don't have the time and the patience to earn some Steems just because it's for Free. If they believe in the project as an investment opportunity and they see the benefits, than they will invest in it. And the people who like to earn some Steems for Free, they will leave Facebook and that kind of outdated Social Media and move to Steemit. And of course, nobody knows what will happen in the future, but I still think that Steem will be a huge Social Media platform, it's only a matter of time. Let's say, we hope! :)