I don’t know why they would do it, but I know bail bondsman often bond people out who they can’t really expect to collect from if they end up fleeing.
For example someone has a $10,000 bond and is basically “judgment proof” meaning they have no meaningful assets. They somehow pony up $1,000, a bail bondsman bonds them out and if the defendant misses his court appearance the bail bondsman loses $10,000.
Why do it? Well for starters, the 10% you pay the bail bondsman is 100% non-refundable. It’s their profit, you will never get it back. If you have a $10,000 bail and you can post the entire $10,000 yourself however, then at the conclusion of the court case you almost always get it back. Even if you get convicted, they will typically deduct court costs, any fine you have to pay and etc, but any remainder you do get back. So the bondsman is basically taking advantage of the fact that typically in a bail arrangement you get the bail back at the end of the trial, but many people can’t afford bail upfront so they would be stuck in jail. The bail bond business takes advantage of this discrepancy, there are people who can pay 10% or whatever and get out, but who have no hope of ponying up their entire bail.
In reality I would think people who have a home or collateral to meet the value of the bail would not be your typical bail bond customers. Most courts will let you use your home as collateral, so someone with assets large enough for collateral probably won’t have to use a bail bondsman in most cases. (In some cases they would, as some courts in some states can insist on “all cash” bond, meaning you can only post in cash.)
But to get back to why bail bondsmen take the risk, basically because making 10% off each “customer” they find that over time the vast majority of bonded defendants make their court appearances and the surety the bail bondsman has on file with the court never gets touched. If you have 100 defendants you bond out, each with a $10,000 bond, that’s $1m in exposure. If 5 of them jump bail, you’re out $50,000. However, you’ve made $95,000 in your 10% fee off the 95 who didn’t jump bail.