I’ve seen that too, but I think cigars are in a different category in most cases, though. The reason I say that is because a lot of pipe tobacco is cased with sugar water, and sometimes that excess sugar will crystallize out, and some people call it plume/bloom, even though it’s not the same thing as is seen on cigars, which aren’t cased. And of course that sugar will be crystalline in appearance. Personally I don’t buy the idea that any crystallized sugar makes a difference in and of itself. I mean, you’re smoking the sugar whether it’s still in the tobacco or has crystallized on the surface, so what’s the difference? I do think it is a sign of age though, and some blends do mellow, meld, and change a bit with age.
Just my hunch. I could be wrong ?