They are simpler and can be read by more devices, especially legacy devices that are still pretty widely deployed. Other than that, not much to say in their favor. They have lower data density compared to 2D codes such as QR or datamatrix. Many linear barcode symbologies have weak or nonexistent error correction capability. But often you don't need that extra data, and the cost of changing processes and equipment to upgrade to a new barcode format is seen as not worth it.
