What's zkSNACKs going to do if they know a user's got stolen cryptocurrency.
I don't think they are going to do anything. Blockchain analysis is mostly a guessing game and trying to connect the dots based on certain criteria no one knows anything about. It's nowhere close to being considered as the absolute truth or any truth at all.
You being n possession of an UTXO that originates from criminal activity doesn't mean you were involved in said activities. There are many ways you could have come in possession of that particular UTXO. It's the same as with paper bills in your wallet. Traces of cocaine on it doesn't make you a drug lord or a drug addict. Money moves from person to person and so does bitcoin. These blockchain analysis companies have created a bullshit business model of selling their interpretation of events and the truth to those willing to purchase it, be that governments or Wasabi and its coordinator.