rake change in ultra turbo sng

Betfair ridiculously increased the rake in ultra turbo sngs overnight. As an example: Yesterday the 6,50$ HU paid out 12,70$ for first place. Today the first place just gets 12,10$ for the exactly same buyin of 6,50$. It is impossible now to beat these sngs over a big samplesize. Why this increase? Thats really rude...