It's all too common for a well-informed drinker to be called a snob because he or she refuses to refer to that sparkling wine from Napa Valley as "Champagne" and scoffs at the friend who traveled to Japan and brought back a bottle of so-called "Scotch" produced in a rural village just outside of Nagasaki. The truth is that where an alcoholic beverage is produced can and often does affect how it tastes. And yes, an educated palate can tell the difference between the genuine article and those spirits merely inspired by it.
Take, for instance, the oft-misunderstood variations of whiskey. Any culture that has grain and a few wooden barrels in which to age it has whiskey, so there are countless varieties of the stuff. For beginners and enthusiasts alike, a good reference point are what I'm calling The Big Three: Bourbon, Scotch and Irish Whiskey.
There are two very important factors that make these three variations distinct. First and most important is actual chemical content. For Bourbon, it's not the real stuff unless it's made with at least 51% corn. This creates a significantly sweeter, thicker whiskey that could never be mistaken for any other. Also distinct is the smokey flavor imparted to Scotch by the vegetable peat drying process.
The other factor is region. You're not drinking Bourbon if it wasn't produced in the United States, but that's not a metric born of jingoism. The United States government actually regulates what can and cannot be called "Bourbon", so your best bet at drinking something that tastes the way Bourbon ought to taste is to get it from its original source. As for the necessity of actually coming from Bourbon County, Kentucky, good luck on that. These days, Bourbon County has gone back and forth with being a dry county, even though it's currently not. And anyway, the area now called Bourbon County, Kentucky was actually a part of Virginia when Bourbon whiskey was invented.
Really, regionalism in spirits shouldn't be that extreme, anyway. People have their favorite sub-regions, especially in terms of Scotch. While the process for making it is essentially the same all over Scotland, where your Scotch comes from can make a huge difference in how it tastes. Chalk this one up to soil content, relative humidity and elevation. Scotland has some pretty drastic variation in all of these factors, so they can and do change the way Scotch-bound grains grow and the way Scotch barrels interact with the alcohol aging inside them. Dedicated Scotch drinkers can easily tell the difference between a Highland malt and one from the region along the river Spey.
As for Irish Whiskey, it lands somewhere between Bourbon and Scotch in terms of body and texture. Because it uses no corn it isn't as sweet as Bourbon and because it essentially never uses peat in the drying process it lacks the smokey undertones of Scotch. Many Irish Whiskeys are known for their potency, thanks to the fact that they are triple distilled, though some Scotch is as well so this isn't a hard and fast rule. In the late 1800's Irish Whiskey was known as a more refined product than its cousins from Scotland and America, though that distinction has also faded with time.
Perhaps no spirit is more reliant on regional quirks to define its flavors than Whiskey. Still, there are plenty of subtle differences in other beverages as well, including beer, wine and special ethnic mixes. Remember that origin does matter and it can only benefit you as a drinker to educate yourself on what makes your favorite potables unique.