1. Protect barcodes: In order to protect barcodes from being stolen or copied, merchants may take measures to cover barcodes with white paper strips.
2. Prevent code scanning: Merchants may not want consumers to know the specific price or other information of products through code scanning, so they should cover the bar code.
3. Incorrect product information: It is possible that the product information is incorrect, and the merchant chooses to overwrite the barcode if it cannot be modified.
For whatever reason, if consumers need to know the specific information of products, it is recommended to contact the merchants directly for consultation.