I am sure that hoarding fabric is nothing new and probably not a healty habit. But, with the cost of fabric predicting to go up to $20/yd, I am very glad that I have a very large stash. My prediction is that there will a lot of trading of fabric coming up in the next few years to be able to afford the fabric we need for our quilts.
It is, however, unfortunate that your friend at her age is still collecting a lot of fabric. What it really means is that when she passes she will have a lot of fabric and supplies for someone else to clean up.
That said, it is her money to spend any way that makes her happy with the days she has left. Who know she could live to be over a 100 years old, like my grandfather, who lived 2 months short of 103 years of age.
More power to her and to you for helping her get organized. That takes a lot of patience.