Yeah, blind cats can somehow feel their surroundings well enough to act normal as if they are not blind at all. Even without their eye sight, they can find objects right in front of them just fine, and they know their way around without pumping into things. It is common for people not be able to tell they are blind.
Not so long ago we have had another blind cat thread. There is a video in there showing a blind kitty playing with a toy.
How was the lady be able to correct over 90 blind cats? Why are they not wanted by other people? There is no reason not to adopt blind cats. They really don't act like disabled. They are just as cute as other cats with normal eye sight.