When you sign a contract with a bail bonds company, it is a private contract that may or may not state that if you fail to pay your bail, you give them permission to hunt you down across state lines. Each state has different laws, rules, or regulations, so the bounty hunter has to sometimes call or research to find out.
More than 98% of people who skip court end up getting found, apprehended, and put back in jail. They use private investigators, skip tracing, and informants along with a reward system for information. They usually find you no matter how clever you think you are being.