Scanned newspapers or newspaper microfilm must be indexed. Indexing is done by a person looking at an image and typing in date, page, etc. It all takes time and time is money. The cost of indexing is generally 5 to 10 cents per image. This is in addition to the cost of scanning.
Software looks at an image and creates a text file.
The text file can vary greatly in its accuracy. This text file can be searched easily and the image presented to the searcher. Some software will even highlight the search phrase on the image for easy location by the searcher. I see a great advantage in presenting to the searcher the original image. Plus, this can all happen over the Internet with a standard browser.