As mentioned, Les and Pam only moved to Albert Square (business and personal premises) in 2014 but they are meant to have lived in Walford prior to that and we first saw Les when he arranged Pat's funeral and we were told he was a local funeral Director who had been used by the Beale/Fowlers before - specifically Pete's as he mentioned it to David but probably Pauline, Arthurs etc.
I don't find that weird. My family have used the same funeral director for all our funerals in the last 30 years - they are based about a mile away but they are still in the same borough and if they moved into our road now, they wouldn't have just moved to the area. They would just have been in a different road in the area before.
Walford is meant to be a London borough like Walthamstow, Stratford, Bethnal Green. Canning Town. There is a lot more to it than just Albert Square, Victoria Road, George Street which we see.