Should we reconsider freeganism?

I use Freeganism here to refer to buying non-vegan items that have been reduced in price. The standard argument in favour of this practice is that since these items are going to waste anyway, purchasing them ensures the animals' lives or produce weren't wasted. I find this reasoning compelling when applied to situations where friends or family would otherwise throw out non-vegan food they won't eat.

However, I'm uncertain whether the same logic holds for purchasing reduced items from stores. A common argument for avoiding animal products is that by not purchasing them, you could be the marginal consumer whose absence causes stores to order less stock. Even though reduced items have already been purchased by the store, I wonder: does consistent demand for reduced animal products signal to stores that over-ordering carries acceptable financial risk? If stores can reliably sell reduced items, maybe this removes their incentive to order more conservatively? 

I'd be interested in perspectives on how stores actually make ordering decisions and whether reduced-item sales factor into these calculations.