a homeless guy at Tottenumcourt road

In London, we an find some homeless people.
It seems to me that there must be some special reason why they choose to be homeless since England is so wealthy and have many supporting system and if people have will, always there is a way.
Maybe they might be treated in a bad way in their childhood and have been hurt and so on.
I feel sorry for them although I never give them changes since I am also poor.
Today, I got a one pound coin on the road. I think I can give this one pound coin to some homeless people since this coin is not mine.
Today I found a homeless guy at Tottenumcourt road and he asked me some changes as he does to all people.
I stand in front of him and put my hand to my pocket to grab that coin.
it is strange, I can not find the coin!
SO I decided to just leave. Maybe that homeless guy understood that I tried to find some change in my pocket but I did not find it. Of course it made him disappointed,
since he expect me to give him change.
He shouted something "It is always like that"
I hope "it is not always like that" for him.