It's a DPOS like many others. Most other coins with DPOS have pools reward for votes, for example it's very common in LISK. I guess the technical level is way higher in LSK but don't worry it will come here the more steem is known.
I have no problem with you keeping a fair share of your witness income. It's just that the situation isn't competitive enough to my taste, which reveals a lack of interest from the really knowledgeable users of blockchains.
With a vote sharing model (which will arrive) the witness are pushed to operate their nodes in the most efficient way ever to be able to propose the greatest sharing possible.
Running a witness is super easy, they are guides to follow with every single steps... you know it if you did.
Is DPOS a scam? that's the real question... full PoS like PIVX or full PoW like BTC. This DPoS is quite scammy.