First, if you look at their market data for the major pairs (BTCUSD, BTCEUR, BTCLTC), you can see that nobody is quoting to fulfill the market maker requirements. I saw this before I started market making, and I see it now. Effectively I was the only market maker.
For example, their smallest level of participation requires 1 BTC per side at <= 0.3%. Current market depth on BTCUSD is this:
http://s14.postimg.org/96j58xzz3/hitbtcdepth.jpg
http://s14.postimg.org/96j58xzz3/hitbtcdepth.jpg
So the current spread for 1 BTC is 296.33 / 300.57. Thats a 1.43% spread, so clearly > 0.3% they require. You can repeat the same process for the other levels and pairs and you'll see that nobody is quoting tight enough to meet their requirements.
Second, if there was some other explanation surely they would have responded to my complaint on their own forums: https://forum.hitbtc.com/discussion/9/hitbtc-not-paying-out-on-market-making-bonuses
They have never responded to me, either publicly or privately to explain why they never paid the money they owed.
I have full logs of my market making activity, and a full email trail of the discussion with their customer rep "Andrus Holm", up until the point at which I asked what had happened to the payment. From that point on, nobody has responded to any emails regarding the issue, and any support tickets I open are just closed without comment.
/Steve