A Handful Of Quarters

I was on my way to work a few weeks ago and noticed that I needed gas, so I stopped at a local convenience store.
While pumping the gas into my vehicle, I was approached by a man about 35 years old and holding a handful of quarters. He said to me "I made a wrong turn and I need gas money to get home."
Now I am always un-trusting of a stranger asking me for money. and I immediately said no. I was in a hurry after all and had just enough time to get to work.
Early.
Like I would prefer.
I could have easily given him a few dollars, or even some change and it would have made no difference to me.
I was not going to be naive and fall for one of those scams that I had seen on tv many times. I was smarter than that. He wasn't going to pull one over on me.
I was not taken advantage of.
I was also very selfish.
Why am I so unwilling to help others when many have helped me?
Why am I so unwilling to give to others when many others have given to me?
He could have been an angel, and I was not aware. He was standing there with a handful of quarters, just trying to get enough money to get home, and I wouldn't help him.
Why am I so unwilling to help others when many have helped me? Why am I so unwilling to give to others when many others have given to m