"Last exit before toll"

I wouldn't call "Last exit before toll" my favorite but it definitely intrigued me.  The story is about a man's battle with his own sub conscience.  Which is something most people go through especially being approached by a stranger asking for money.  With so many dishonest or lazy people pan handling it's hard to differentiate between them and someone in genuine need of help.  The man in this story dismissed the woman and as he drove off he began to doubt his choice.  So often I have the same battle internally feeling guilty as though I was the one who caused their situation.  As the character returned to help the woman she wasn't there. But, he did question the "dark cab of the semi parked around back."  That line is where I was hooked.  I find myself wondering what extremes these people asking for money go to in order to get it.  Was the woman doing something unethical? Was the woman even in the dark cab?  It was a cliff hanger that I myself wish I could answer.  The man ultimately blaming himself feeling as though he could have been her solution.  Instead he may have been the cause of her unethical decisions maybe...