>Converting these mixed coins on a large scale to something like dollars is very very hard. Most exchanges that interact with the traditional banking system do check where you got the money from. It's not like you can send $1M worth of tumbled coins to Bitstamp/Kraken/Coinbase and convert them to dollars without tons of paperwork. And it's not like you can buy a house/car/boat with these coins and expect the IRS not to show up.
This nicely explains why the Mexican cartels (in their simplicity) used US dollars and not Bitcoins ;).
But I still wonder about the paperwork, it completely escapes me.
I mean, there are mainly three "legit" ways to actually become in possession of a Bitcoin:
1) mining it
2) buying it (i.e. giving real money in exchange for it), let's say as an investment
3) accepting the Bitcoin as payment for any service, good, etc.
Why any of the above (that have more or less a proven/provable origin and thus that can justify the provenance of the Bitcoin and somehow do the appropriate paperworks) would want to use a mixer?
Or - differently put - once you Bitcoin has gone through the mixer isn't it not anymore suitable to any exchange requiring this paperwork?
I.e. it becomes "unspendable" money (if not in very small quantities, small amount single operations, limited quantities of operation).
Or am I missing something?