Fresh food is supposed to be fresh, which doesn’t really combine that well with dollar stores’ business model. They buy fruit and vegetables in large quantities to get the lowest price possible. And then, they sit on the shelves until they are sold.
That’s why fruits and vegetables often taste funny there. To be more precise, they have no taste. It’s because they choose hybrids that have a long shelf life. Scientists have managed to achieve an extremely long shelf life for some products, but the taste was sacrificed.