The whole sugar/wine shortage thing is really more about cause and effect than about imports. Brutal slavery led to a revolt - makes sense. A revolt led to a loss of an important product - makes sense. Loss of something vital led to an uprising - makes sense.
What about your adventuring activity? What if your PCs go out and destroy a horrible slave trading business that has been stealing farm girls and turning them into cotton picking slaves? Well then there will no longer be those cotton picking slaves, which means there will no longer be cotton, which means that cloth and clothing will become either scarcer or really more expensive. This may not end a king’s reign, but your player characters will have just affected the economy of their homeland.
Game example that happened in Fletnern - What if your PCs come up with a way to hunt and kill a large number of mastodons? All of a sudden, ivory is flooding the market. Well, pretty quickly, the price of ivory nose dives, and their hauls, while still valuable, are no longer as valuable. This probably wasn’t that important of an issue, but I do have to keep track of the fact that ivory will never again be as valuable as it indicates in my own rule book.
Think smaller - campaign starting mission is to wipe out the wolves that are harassing the shepherds in the region. OK, they succeed and kill dozens of wolves for the bounties. Well, next year, either the deer and other prey animals are going to have a population explosion or some more dangerous critter is going to move into the wolves’ territory. Same if they wipe out a neighboring group of bandits, outlaws or raiders. Soon enough someone is going to move in there.
This can actually be easy for you as the GM. Draw up a ruined castle. Stock it with low level bandits. Send in the PCs. A year later (game time), restock it with mid-level orc raiders. A year later all this bloodshed has caused some undead to drift out of the castle’s catacombs and they are now terrorizing the countryside, possibly with their cult of freaky followers. One map, three adventures, the dominoes all fall in line.
The moral of this story: Don’t let your players’ actions happen in a vacuum.