Episode #2.8 - S2-E8
Officer Dwayne Myers: Chief, will you take off your detective head? You're amongst friends now!
DI Richard Poole: If I find out that you broke into that post office...!
Officer Dwayne Myers: Don't worry...You won't find out. (00:42:40)
Answer: Most likely they had only tropical exotic drinks, he wanted an old fashioned English beer.