There are very high regulatory costs if you're going to run a book/tote and pay out people's bets. But yes, your data could be worth more than your bookmaking margins. If it's worth buying, it's worth using yourself. I like the idea of a private prediction market, something between kaggle and that investment fund that uses homomorphic encryption, the name escapes me. 'Invest' on betting markets, return a share of profits to contributors.
Sports betting and/or prediction markets are such an obvious application of cryptocurrencies/smart contracts that I'm kind of shocked it isn't already a huge part of the darknet (or maybe it is and I just don't know about it). It doesn't even have to be good, as long as it's anonymous, decentralized, and eliminates counter-party risk. Something like that could be adopted at a glacial pace and still be unstoppable in the long term.
I thought about as soon as I heard of the technologies. There is the one part, validating results of sports events to initiate payouts, the setting up of new events, that would seem to make it more difficult without some sort of scraping, or intervening party.