My older son (now 6) wouldn't sit very long when I read to him when he was little. He would do pretty much the same thing as your daughter. BUT, at a very young age he would "read" his books also for long periods of time. It was part of our nightly ritual to read to him, but there were peroids that we skipped it b/c he just wouldn't sit for it.
My son started reading site words before he was 3 and was reading at almost a 2nd grade level going into kindergarten. He pretty much did it all on his own. There was a time (around 3) that he had us point to each word as we read it to him. We learned later that was his way of learning to read.
So, what I'm saying, it sounds like she has some interest in books, and that's good. Her approach may be different, but she doesn't sound like she's completely not interested. Give her simple books that have pictures with words that match. If she's looking at them on her own, those kind of books don't matter if you don't go in order.
BTW...My younger son (now 3) LOVES to be read to, but he definitely is not as far along in "reading" as his brother was at this age. They all approach it differently!!