General question regarding 506b/506c passive investment platforms

[Thomas Loggins]

Like any investor "wanna-be", I read a lot and listen to podcasts of syndicators and sponsors (GPs, I assume) who pool capital from passive investors to target value-add multifamily opportunities. 

While I have significant experience on the debt side of multifamily real estate, I don't have a lot of experience on the dynamics of syndicating equity. I understand in general how equity relationships work (GP vs. LP, active vs. passive, preferred returns / promote, etc.) as I have to review operating agreements at times and I have reviewed promote waterfalls. But I am not an expert.

My question is: Why would these online, value-add investing platforms need or want to reach out to "mom and pop" investors, accredited or not, to raise capital? 

In most of the deals I see, underwrite, asset-manage from a lender perspective, I see the same sponsors raising equity from the same known investors deal after deal, without the need to reach out to the general public for equity contributions. I will note that pretty much ALL of the deals we finance are institutional-quality properties with exit strategies of either 1) refi via long-term, permanent takeout (life companies), or 2) sale / disposition to institutional investors.

So as I individually attempt begin my personal investing career (currently in learning mode with capital ready to deploy), I understand that I can't just walk into a room full of sophisticated, savvy and experienced investors and announce that I'd like to participate in a "sure thing", ground-up 350-unit, class A apartment building in midtown ATL. I get it. 

But why would these online, value-add strategy platforms need or want my equity contribution? Do they not have access to the more sophisticated investors? Does the equity that would be provided by such savvy and experienced investors demand demand higher returns than mom and pop can demand (i.e. more expensive equity)?  What else?

Thanks in advance for any comments.