It's part of studying the brain's processes.
It's useful in understanding how we read words, how the brain performs the task. This is important in understanding, for example, why poor readers perform badly, why some people are dyslexic, and why some people who have suffered some brain damage sometimes fail to recognise some words or lose some ability to read and also why many don't. Many well-educated people are poor spellers.Why? If we know exactly what happens when they try to recall the spelling of words which they've seen many times, yet it doesn't happen to others, we'd be learning something about the brain's working in each case, which may have wider implications in medicine.
Studying the brain hardly seems as waste of money.