The 10% allocated to SPS is not given to Steemit Inc.

The SteemDAO was a concept proposed by @blocktrades to allow Steem users to publicly propose work they are willing to do in exchange for pay. Steem users can then vote on these proposals in almost the same way they vote for witnesses It uses stake-weighted votes, but voters can vote for as many proposals as they want.

https://steemit.com/steem/@steemitblog/hf21-sps-and-eip-explained