I have to agree, unless you make numerous trips past, or work adjacent, it is indeed hard to know how long someone has been there. I would like to think that a few have approached her. However there are a lot of people like this 'known' to the local police. The police tend to keep an eye on them and leave them to their own devices most of the time.

Some people have very complex stories, and while they appear to beg for interaction and attention, in fact want the complete opposite.

That said, well done for being one of the ones caring enough to approach and have your say about the matter. I usually keep myself to myself, but like yourself, when distress is obvious, will always make a point.