"There she was" had two intentions. Primarily, V1 describes a young man going about some fairly regular activities that commence a Saturday. Then the tonal mood changes and the singer says "There she was." Which is really a question for a listener...There who was?
Drama, suspense and all that.

And then I never gave her a name just described her beauty, what she had done and why she was there. She remained "she."

Also, in a long Story song with more than 2 verses, "there she was" was a a turn from the end of one verse back into the beginning of the next. And relieves a bit of the monotony.

So......"there she was." wink

https://soundcloud.com/sunset-poet-of-texas