Quite possibly reflecting a very-long term historical trend.
I'm currently involved with a project studying all the known licensed premises In Ceredigion (the old Cardiganshire) over the last couple of hundred years. (It's a tough job but someone has to do it)
Official figures show that there were about 450 licensed premises (beerhouses, pubs, inns, hotels) in thee county in about 1860 (adult population 63000) - plus uncounted unlicensed drinking-dens in the hills. By the early 1900s it was down to about 300. Probably less than 150 now.
Part of it was deliberate government policy. They somehow felt that one boozer per eighty inhabitants (in some of the market towns) was a few too many. They introduced a levy on all pubs, and used the money to pay compensation to pubs that they shut down as being 'unnecessary'. It was just half a dozen or so a year, but it adds up.
And as people drink a bit less then marginal pubs in rural areas close. So people have to drive....'nuff said.
Times have changed - I found one wonderful tale of a bod in Cardigan who was up before the beak for drunk and disorderly for the 38th time!
More details, if you're interested, at http://pint-of-history.wales