Never could drink that stuff. One bottle and have a headache—the only beer that does that. I have heard the same from many others. Budweiser also use beechwood to brew the beer, something also not in the purity law.
Beechwood.... phew.... one twig in how many gallons of brew?
"Beechwood Aging" means that beechwood chips are added to attract yeast as a coating, thereby allowing more yeast to be in contact with with beer (wort?), rather than pooling at the bottom, during fermentation.
Beechwood does not add any flavor to the brew.
Popsicle sticks are beechwood.
I've heard that aluminum pellets can accomplish the same thing as beechwood, but from taking up bread making recently, all the texts frown on the use of metal and yeast for kneading and proofing, at least sourdough yeast and non-stainless metal.