Bonds, as I have seen them, are either a crutch for an operation that lacks integrity or a reaction, in fear, to punish those that follow the guilty
As you have seen them, possibly
Pilot & Apprentice but generally pilots only have themselves to blame for bonds, usually brought about because people have taken an endorsement and scooted off!
What bond-jumpers don't always take on board is that they are a marked man in a relatively small market place and companies do talk to each other, even that is not always necessary, just a glance through the log book will tell its own story!