Maybe it will not be the best place to shop - the conditions are not the best, and the malls are too competitive - but the municipal market, squeezed in the centre of town, is a classical place, interesting, at least, to see, mainly when activity is strong.
Maringá is a shopping center where crises led to many closed shops, but still with some movement. Adjacent to it there's the best parking lot in town (paid but not expensive).
I don't know what keeps the first mall of Leiria (and one of the smallest), still working. Maybe the quality of some shops, as this one, where I got the best prices for a new laptop recently bought.