and in reality what other reason is for a person to have a book read to them?
quite a few infact:
Lots of members of the same family might want to read the book without having to wait until one member has finished with it...so perhaps it was read by one member to the rest of the family so they could all experience it together..
or, as an example....my g/f is getting to the end of the last book of 12 in a series and while she was cooking dinner last night I was reading it to her as she wanted to get to the end...btw, she doens't have a disability and is very highly qualified.
I'm sure if you think about it there could be several reasons why someone might have a book read to them other than them having a disability.