Steemsports has a team of 7 people producing content and developing the business built in the Steem ecosystem and on top of Steem (unless this sort of hostility drives them to focus their efforts elsewhere, and frankly I wouldn't blame them). They've been at this for months. For that, what you call 'rake' is accumulation of $17000 worth of SP.

In fact, Steemsports is participatory content more than actual gambling and the 'rake' is nothing of the sort. They are earning SP based on contributing content that draws participation, and based on the subjective view of many stakeholders that their model of participatory content is a positive for the growth and success of the platform as a whole relative to to other content such as poems or essays. In this case the participation takes the form of following, voting, wide distribution of stake, and some 'fan' comments.

The stake and rewards that are distributed to the actual voters are so small that calling Steamsports' earnings 'rake' is a mischaracterization; in fact they are rewards for Steemsports effort/work in putting the whole thing together and running it, including the posts themselves. It is similar to the profit margin McDonalds makes when they sell you Coke which has a game ticket attached to it. That's not rake.

Disabling curation rewards is not a good solution to anything (unless, possibly, done globally). Doing so means that voters have to contribute their valuable and scarce vote power and receive less back for doing so than they would voting on something else, potentially of equal or even lesser value. I actually think curation reward are currently too variable just using the existing formulas and result in perverse incentives along these lines. However, suggesting that one particular form of content disable them makes this worse.