[jayrot]

Not necessarily. There are different styles and reasons for money laundering. Selling overpriced items (and colluding with buyers) is a good way to "launder" the provenance of money. Works perfectly fine in online, electronic transactions. The clean money comes from legitimate sales.

[jldugger]

Help me understand how this works. You have a big pile of money from illegal sources. You list fake rare books on Amazon for a million dollars. How are these connected? If you give the dirty money to the "buyer, they need to deposit it in a bank in order to pay Amazon, and will be subject to the normal bank rules.

You need someone who can safely pass your money from paper to digital. The only people who can do this are folks with substantial paper money flows. Think cash-only restaurants. They report a modest growth in business, deposit your cash, and "buy" goods and services from you. But you can already fake this as a restaurant supply vendor.

[tomatotomato37]

You're thinking too old fashion on this. A large amount of black market activity now happens entirely digitally, either via stolen credit card numbers, illicit deals on the dark web, or highly questionable cryptocurrency schemes. All those sources need a way to make their profit look legitimate and thus utilize tactics like this.