As freelancer I was bringing up the discussion with my peers at a company about the amount we were getting paid.
Recruitment kind of worked like the following: the company that we were all employed at just paid a fixed amount per freelance developer. And the developers all got contracted through a preferred supplier. For development jobs the amount per hour for a freelancer was capped at around 90 EUR. The preferred supplier wanted to get at least 10 EUR per hour, so this meant the maximum a dev could earn was around 80 EUR per hour.
However often other recruitment companies would place developers at the preferred supplier, so they wanted a share of the cut as well.
One dev had the preferred supplier and 2 recruitment companies between himself and the company we worked at, so he earned only 55 EUR an hour.
Once we realised that for the employer it didn't really matter how much people earned, as long as it was no more than the hourly rate the company was willing to pay, all of us increased our rates at the next term, at the cost of the middlemen of course.
However, the recruitment company that hired me told me I could get one final raise, but I was forbidden to discuss remuneration in the future with my peers at this company.