Places like Dollar Tree, I'll buy prepackaged, shelf-stable candy, cookies, bottled pop, etc. I wouldn't buy fresh food because I don't trust it.
That being said, I don't trust a lot of stuff at
Walmart because of the number of perishable, refrigerated or frozen products that I've seen stuffed on shelves, displays, etc. It's not even a once-in-a-while thing, either. I see it every single trip and it disgusts me. And I wonder how many workers or well-meaning folk go by and put that stuff back in the freezer/refrigerated case? I've had food poisoning and don't care to repeat it.
I bought cream cheese there once that I went to use and it was super wet and chunky, like it had frozen and thawed or sat at room temp and then was refrigerated again.
I do buy stuff at Dollar General, especially the milk or cream, and shelf-stable products like chips, drinks, sauces, cereals, etc. It's the closest store to my house and rather than trudge through the Mega-Huge grocery stores or fight through the zillion people in line at Aldi, I'll just make a quick stop instead. I pass two on the way home from work, too, so convenience is a factor.