Personally I would think are there consequences along with drinking a lot of alcohol. Is he able to function. Does he do other things other than drink beer on the weekend. If nothing else is getting done that's a consequence.
Right now he's young, probably in the early stages of something. As his body ages or is progressively trashed it will catch up to him. I've seen the consequences of those that started drinking/partying in their teens. A couple of decades later they are still acting like a teenager. Maturity stops at the age when heavy drug or alcohol use started.
Also saw several articles over the last year on binge drinking. The numerical threshold is lower than you would think.
Binge Drinking Isn?t Just for College Kids Anymore - Bloomberg Business
Opinion, your reaction sounds correct. 24 is a lot of anything.
Good Luck