EXPORT, Pa. -- Mary Bach did it again.

The Murrysville woman has been acting as a consumer advocate for several years, and often takes big retail companies to court when she finds errors at the checkout counter.

On Monday morning, Wal-Mart decided not to fight Bach's latest lawsuit, so District Judge Charles Conway ruled in her favor and awarded Bach $100 for being overcharged on a $2 purchase at the company's Delmont store.

Conway gave Bach another judgment against the same store on May 28.

Bach said she sued because she alerted management about the error but the price scan was not corrected on her subsequent visits to the store.

Though the $100 award is relatively minor, Bach said it's not the money that's important to her. She wants shoppers to be aware that mistakes can happen, so they should check to make sure that the advertised price is correctly scanned at the checkout.

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Click here for a PDF listing of Allegheny County supermarkets and convenience stores that participate in the Scanning Certification Program. If they overcharge you for an item, they will give it to you for free (up to $10).