"In 27 years, I've drunk 50,000 beers"

This line from the Silver Jews' song "Trains Across the Sea" has always intrigued some people. But what are the logistics of this claim? Is it realistic? How many beers per month, week, day would it take?

On the face it, not all that many:

50,000/27=1,851 beers/year
154 beers/month
35 beers/week
5 beers/day

But was he drinking all 27 years? Generously assuming he started at age 15, credulity weakens slightly:

50,000/12=4,167 beers/year
347 beers/month
80 beers/week
11 beers/day

If he was scrupulously legal and started drinking at age 21, however, the schedule acquires another magnitude of rigor:

50,000/6=8,333 beers/year
694 beers/month
160 beers/week
23 beers/day