The laws aren't universally the same in all countries. Copyright/product counterfeiting can vary from country to country for instance, so you can do something legally in one country but the importation of such a product into another country would be illegal. China makes all kinds of knock-off DVDs and products, while US resellers can get themselves in a bunch of trouble for importing and selling such products. Large scale US resellers get arrested for selling these Chinese knock-offs, but it doesn't mean that the Chinese manufacturers engaged in a legal activity in their own country are at risk of being arrested and deported to the US even though they're the bigger fish.

With your bridge example different countries and jurisdictions could have different requirements for the purchase of real estate or that you even were buying real estate rather than like an NFT, toy model, etc. A scam in the US might not be considered a scam in a foreign jurisdiction and even within the US it might not be considered a scam, like if someone offers you a quit claim deed for whatever interests they have in a bridge for $20 that could be considered legal depending on what representations were made. In fact a person buying a quit claim deed for way below market value could find themselves in hot water being investigated for like elder abuse with them being seen as the one trying to pull a scam on a potentially vulnerable property owner.