Mould is not like dirt that can just be rubbed off the product. If a package of strawberries has some mouldy berries in it, then that mould has already spread to its neighbours without being visible. All they're doing is repackaging the berries that don't have any visible mould on them, and that mould will grow very quickly.

If you buy a supposedly "mould-free" bundle that was repackaged from a mouldy bundle, the entire batch is likely to rot within a day or two of purchase.