This share based system allows users to make the odds and anyone to add liquidity to a market. There are different ways to set up a decentralized sports betting platform, however a common way of doing this is through a paramutuel betting system, or a prediction market. They are also cheaper to run than a traditional bookie, so they should be able to cut down on the spread normally given to a bookie, thus making it cheaper for all parties.
These contracts live on a blockchain so they are transparent and auditable. Instead, coders have built little escrow contracts that can hold people’s money, find out who wins the game, and automatically pay out the winners. With decentralized sports betting you don’t have to rely on a bookie to hold your money and make payouts. Furthermore, they utilize oracles to bring sports data on chain in real time so that they can autonomously make payments to winners.