Very true. Unfortunately much like a great many other "minority" hobbies there just isn't the demand for bricks and mortar shops any more. The long running Comet Miniatures in Lavender Hill even shut down last year. Modelzone was a bit rubbish but at least you could, as you say, go in and just have a look.
There's a little modelling shop next door to the comic book shop I frequent (yes I am THAT geeky) and he sells all kinds of good stuff by way of supplies but there never seems to be anyone in there!.