Not sure how it works in the US, but here in Oz anti money-laundering laws state that exchanging gold with value over $10 k (dollarydoos) requires gov’t paperwork [1]. So an explanation might still be in order.
A 1 kg bar is a smidge over 32 Troy ounces, and gold has a spot prices hovering around $2k (US) per Troy ounce. Enough that questions will be asked anywhere reputable, and a significant commission will be paid anywhere else. I’m not familiar with typical money-laundering commissions.
[1] In Australia, those same rules apply to cash as well as other outside-the-banking-paperwork tokens of value.
