Maybe. So what? There are many Ubers, AirBnBs, Googles, etc. Diversity and competition is very valuable for consumers. It keeps innovation moving forward, so I really don’t see your point here.
It is ironic, how on a post about a website that encourages competition at the employer level for providing fair wages, people are complaining that they don't need competition at the meta-level (salary-sharing websites level).