Why do you think only 1 in 6 try to get their cash back? Didn't one of the guys involved in thr have a story about losing a pile of cash that way??
Lawyer's fees. Intimidation. $1000 retainer and $200/hour to fight unlimited lawyers to get $2000 cash back for a lot of it.
Actually believe those dumb ass releases they bully you into signing for some of it.
Some of it actually is ill gotten cash.
Probably some other things I haven't thought of.
I understand the legal and tactical ramifications of fighting the police, but I can't think of a
moral reason not to track the officer that stole your honest money down and get it (or like value) back from him.