Ann: Arafura Share Purchase Plan Results, page-27

Oh, that’s easy to answer. Money. Sophisticated investors can bring millions to the table with only a small number of people, and relatively little work from the company. Retail investors are generally tens of thousands at most, and the company needs to provide a prospectus to allow retail investment.

In other words, it’s the regulatory framework that tilts the playing field - it’s easier to raise money through sophisticated investors and SPPs than to do the hard (and expensive!) work to give retail investors a fair chance.