The shop, it must be remembered competes in turn with the marketeer in all sorts of ways. Permanency, guarantees, after sales service etc. However centre management and market management should be able to influence the product mix to achieve optimum variety. There is an unsubstantiated myth that marketeers compete the easy way and on the cheap. One can see that the marketeer can pay a relatively high rate for space, and without the certainty that the place is always available.
Some markets have an entrance fee, possibly discouraging some customers from entering.
Marketeers must be tough people if they are to make a living. Any suggestion that the playing field is stacked against the shopkeeper is therefore likely to be untested rhetoric. Management and advertising. Like a shopping centre, a market may be managed well or may not. Management may have frequent advertising campaigns and extensive operational rules, or just collect the stall and entrance fees and put up the fence.