The Bowling Green Inn is next to Tesco's, but he could quite easily have drunk at the Castle House. But then he could also have drunk at:

The Whtehouse
The Cock Of Tupsley
The Rose and Crown
The Entertainer
The Booth Hall
The Grapes
The Litchfield Vaults
The Kerry Arms
O'Neils
JD Wetherspoon
The Sun
The Barrels
The Bay Horse
The Belmont
The Ship
The Treacle Mines
The Buckingham
The Brewers Arms
The Horse And Groom
The Market Tavern
The Spread Eagle
The Heart Of Oak
The Oxford Arms
The Rose Gardens
The Salmon
The Victory
The Wye
The Britannia
The Foxhunter
The Nell Gwynne
The Old Harp
The Volunteer
The Swan
The Imperial
Saxty's
The Liten Tree
The Bridge
The Sawyers Rest
The Volunteer
And any other I've failed to think of.