Isn't the argument that fair markets are what allow all that stuff to get done? In other words they are better for the group over the long term. Unfair (via corruption or whatever have you) markets tend to stagnate and are good for the individual in the short term (eg within their own lifetime).

Also, who wants to haggle over strawberries every single time you shop? There's a definite time cost to having to "discover" the price on every single transaction.