You make several assumptions that they have someone in the first place, and that they care about them as well - but justice should never be about assumptions. The entire justice system is designed to let guilty go free if it means a single innocent person is protected from wrongful incarceration.

Why do you think involving innocents is a good idea? Especially when it means they go to jail and get their freedoms taken away? People who skip bail already put their family at risk plenty of times, often signing away property and leaving family members destitute.

It would be much better to refund bail costs for anyone acquitted than to force this on people who do not deserve it.