Meh, we're mostly on the same page. I wasn't thinking so much of legit authorities acting. More like someone will want to steal that gold. Best to keep it on the down low, dole it out slowly, kinda like money laundering. Avoiding the thugs vs. avoiding the authorities? Am I making sense? I have no idea any more.

By whom, exactly? The states too weak to invade and take control of pirate havens?

If they landed in a legitimate port they will ask questions. States were weaker back then, but not that weak. BTW, much gold was brought back not as bullion, but as personal jewelry, because jewelry was not taxes, but stuff like gold nuggets or gold bricks were.

Also they didn't care to tax pirates. If you were a 'real' pirate, as in someone who did not have a letter of marque, you were liable to hanged and everything taken from you. If you were a privateer you paid 10% of your 'earnings' to the crown and kept the rest. I should mention that earnings weren't just precious metals and stones, they were EVERYTHING. If you plundered a ship full of sugar cane and tobacco, the crown got 10% of that.

It does depend on your time period, if you were active in the 1640s to the 1660s, the golden age of piracy, even if you didn't have a letter of Marque, it was likely that nations did not care if you were a pirate as long as you didn't rob THEIR ships. Political tensions were super high in Europe at the time and there was a doctrine of 'no peace beyond the line' meaning if you went to the West Indies, it was a free for all. So if you were an English or French pirate and robbed only Spanish ships, the French and English didn't give a fuck and you go back to a French/English port and no one would bother you. But if you tried to do piracy in the 1690s to 1710s, you were going to get hanged. This era of piracy is when navies started to spring up and they didn't tolerate any form of piracy on the high seas at all, and the concept of no peace beyond the line ceased to exist. Many of the most famous pirates we know, like Black Beard and Calico Jack were active during this time period.

The most successful 'pure' pirate (someone who did not operate with a letter of marque) was Henry Every, and he wasn't in the Caribbean, he robbed a huge ass treasure ship belonging to the Mughal Empire in the Indian ocean and he and his crew stole a ton of treasure. The thing which is just as fascinating is that Henry absolutely got away with it. He fucking disappeared into thin air and was never found with his share of the loot. I know finding someone was harder in those days, but even back then being a fugitive was difficult, and a super high profile fugitive like him (his pirate action caused a huge diplomatic crisis between England and the Mughal Empire) would not have been allowed to stay on the run for long.

To give you an example of how that is different, Piet Hein, a Dutch pirate, also robbed a Spanish treasure ship, but due to the fact that it happened nearly 100 years prior to Henry's action, he had the backing of the Dutch state (which was at war with Spain at the time) and he was richly rewarded for it instead of being hunted.