If you go back a bit further, you'll see the "Voat needs an angel" thread where money was really a tight. Suddenly, Putt doesn't even want donations to pay for hosting?

If you would've had the opportunity to follow discussions in /v/VoatDev & seen all announcements, Putt did mention that with Bitcoins growth the money amassed after that funding drive is still paying for the lowered operating costs.

As for accepting donations at the moment, keeping in mind what I just said, I think @PeaceSeeker explained it fairly well & with my business experience it is logical.