Why are so many Scotches called "The [blank]"

The Macallan. The Glenlivet. The Balvenie. I’m sure there’s more…

It’s just Scotch – there’s no such thing as The Stolichnaya or The Patron.

Any ideas?

Scottish clan chiefs and lairds were often referred to as eg “The” MacGregor, of (Clan) MacGregor. I guess the whiskies use this as some sort of faux-authenticity thing.

As far as Glenlivet is concerned, it dates back to a copyright fight over the name. The original distillery started calling themselves The Glenlivet, and other distilleries were permitted to use the term only as a hyphenated name (Glen Moray-Glenlivet). My guess is the others (there are only 5 by my count) copied the phrasing when they founded their distilleries.

I checked the Wikipedia article for Glenlivet, and found a historical reason why the product is marketed as “The Glenlivet”:

It seems to imply that the Smiths tacked on “The” at this time to distinguish their product from that of other local distillers.