We're currently in a system where if a poor person does the wrong thing, a wealthy person has to cover the tab.
On the specific topic of bail bonds, one major argument is that rich people are gaining an advantage in comfort from their wealth - which I think is perfectly reasonable, given that is explicitly the purpose of wealth.
A second major argument is that the system is unreasonably harsh to the poor. Probably true, I don't know. But that isn't an argument I'm dealing with - I'm pointing out that wealthy people buying comfort is the complaint at the root of the threat and it isn't a strong complaint. Because that is what wealth is for.
> I can't imagine whatever costs you're imagining are involved in tracking down people skipping court dates would tax the rich out of their privilege.
People need to control more money than they spend so they can set themselves up for retirement. "This would just come out of their savings" is also a bad argument at all levels of the social tree.
That isn't really going to the point you raise, which I am going to leave alone, but is an aside that I think that argument is fundamentally bad because it could be repeatedly applied until it turns out you misread the future and people start running out of savings.