The burden on his parents is that they're deprived of the use of their $500,000 cash deposit as long as sonny boy is out on bail. When bail is set low, some people choose to procure a bail bond from a bondsman at the cost of 10% of the amount of the bail (i.e., $50,000 in the case of Barry boy). That premium cost is lost to the family even if the defendant shows up for all court appearances, so Seltzer's parents deposited the entire bail amount with the court to save the premium.
My suspicion is that Seltzer will not get a long sentence when convicted. He ought to be in jail just for being stupid since the first story about this crime indicated that Seltzer came down to the police station and blabbed everything to the cops.
All the judge wants to do is make a name for himself so he can get appointed to the 9th circus pimp court.