The scavenger hunts are not worth it unless you already happen to be there or you have the item at home. Most of these are discontinued, seasonal, or mis-entered items. The few I was successful at finding were at a locally owned store for a specialty snack brand, and for a few holiday items at Dollar General. I would say I have about a 5% success rate.
The customer service audits are a good add-on. They add less than 10 minutes if I am already there.