These market type places are a left over product from the seventies..and bear very little relationship to the modern world. They thrive or did in South London for example. I remember a particularly good one in Tooting...seedy but effective. But as prices fell with the rise of the supermarkets to massive scale, their real relevance evaporated, so its very hard to see these places succeeding. They can neither compete on price or quality. The Tooting one is probably still there and still doing well, as it is surrounded by a high density of population who dont need to drive to get to it.
Once driving comes in to the equation then everyone goes to Tesco. Its a well known fact that car manufacturers pre program their motors to head for the nearest Tesco. It works by homing beacon..it draws the motorised vehicle there like a giant magnet. Plus... the sure fire fact that there are no parking charges works like a magnet on the driver.
Surely that one in Pencester cant survive much longer. There was one of these markets open here in former times, a little past Market Sq heading seaward. Its been closed and boarded for a long time. The Charlton Centre, in similar vein, struggles from hand to mouth also teethering on the brink...so clearly the model doesnt work in the modern era.