In case anyone reading my post above doesn't recognize sarcasm (Sheldon):
I've experienced one issue in my life, and that was regarding a subsidiary of Millennium Sports called Wagermall. The owner of Millennium had the audacity to go on CNN and say he wanted to be legalized in the US and pay taxes; he said the US regulations were out of touch with the rest of the world except for conservative Middle Eastern countries. The next week, while his plane touched down in the US so he could catch another plane to Europe, he and his travel partners were arrested and their laptops seized. Some arrangement had been made by US authorities with other Millennium principals at their base (I happened to have a client who knew the guy who leased them their buildings), so the people there betrayed the owner and made off with all equipment and locally stashed money, likely in coordination with US authorities. I say likely because while the owner's plane was in the air, they started taking the computers and other equipment out of the buildings.
I got caught with between 11K and 12K in Wagermall, which went up in smoke. I had kept it there off-season because I was earning 10% a month interest at the time by doing so, but it was fraction of what I had there in-season.
That was the one event in 25 years. Nobody on the lists on the seized laptops got in any trouble.
Unlike Dan, I have dabbled in boutique books, and have never experienced an issue. I've had offshores sort of shut me down by putting extremely low limits on me, and I did have one tell me that I don't "fit their customer profile," so they dropped me but paid me, but those things happen in LV, too. The place that said I didn't fit their profile eventually reconsidered and allowed me back. Most books will do so, employing a piggybacking attitude -- "if you can't beat 'em, join 'em."