Skipping out on a bond is rarely a good idea and usually catches up to people. Since this is a theoretical question, I will simply tell you how the process generally works:
1. When the court finds out that a person has left the state they will then issue a warrant for that persons arrest and will declare the bond forfeit. Any money that was given to the bondsman will then belong to the bondsman and the bondsman will be able to exercise their rights against any leins that they may have obtained.
2. The bondsman will be responsible for paying the debt on the bond to the court after 120-150 days. Generally, this is the step where bounty hunters get involved. The bounty hunter is tasked to find that person and drag them back to the jurisdiction where the offense was committed.
3. After 120-150 days is up the bail bondsman must pay the court the full amount of the bond if he cannot produce the defendant. Should the defendant successfully manage to elude a bondsman and the bondsman pays the courts he will still have a warrant outstanding for his arrest, but the bondsman will not still be looking for him. This state of affairs is extremely rare though as most often people are found.
In answer to your other question, generally people who try to leave the country and have warrants out for their arrest ARE indeed placed into custody and returned to the jurisdiction where they have a warrant out. The person you knew may have had a warrant out for a less serious offense.
I hope this answers your question and helps out with whatever trouble you may have. Best of luck!
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