I was an exchange student in the US, and was on my usual morning walk to the department when this big homeless man stopped me and asked for money. I felt bad, but told him no anyway, since I didn't have any cash on me. I kept walking on, but my gut instinct told me I should have done something to help the guy out. I remembered I had a protein bar in my bag, so I figured I'll give that to him instead. At least he'll have a bit of something to eat.
So I grabbed the bar, walked back and found the guy panhandling not far from where I first met him. I went up to him and kindly offered him the bar, explaining that it was the only thing I had to give today. He looked at me angrily and shouted "You can shove it up your ass!" with his thick American accent as he walked off.
So yeah, not listening to my gut too much these days anymore.