Well, the survey is aimed at women over 40. And that is over half a lifetime for many women and that means we are a substantial market and many of us are avid readers, used to sustained reading and reading whole books.
I think the publisher is seeing older woman, as not so much as a niche market but as a potential large and lucrative market if they can find out what sort of books attract us. In recent years the 'chick lit' market has boomed. Novels written about women under 30 or in the marrying/child rearing age group for readers in that age/life bracket have been a nice little earner for a lot of publishers, and they are now trying to find out whether older women would also get hooked onto books about their lives, people their age and living similar lives and it is good to see any industry, other than incontinence aids and stair lifts seeing us as a market to be targetted rather than ignored.
This strikes me as a sound business proposition. However if what they are really looking at is the fiction market, and why not? Then they should have presented the questionnaire as being about our fiction reading; what kind of novels we read etc. Instead they presented the survey as (we) would like to find out more about you and reading: how often you read, what you like and don't like reading, what makes you buy a book or puts you off altogether. which suggests a far wider survey of our reading habits.
If I had realised at the start that the survey was all about fiction, I wouldn't have spent time answering it, as I read so little modern fiction.
However, having presented it to us as a survey of our reading habits and then narrowly concentrated the survey on what fiction we read, the implicit assumption is that women only read novels, so all those non-fiction books must be for men and we shouldn't worry our pretty little heads about those big tomes on subjects that will not interest us.