I am sure if its a real problem for you they would exchange them. The cashier's are pretty dilligent at checkimg the pkged produce but sometimes its hard to see from the outside. I generally just throw out the bad piece and be greatful they have produce that is pesticide and preservative free.
Trader Joe's gets there fruit from farmers which don't use a lot of chemicals which usually preserve the fruits for about a week. I had the same issue, but then quickly realized that I need to consume the fruits faster.
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