I usually shy away from threads that go this way (well, except for the ones in which someone has placed him or her self in front of a train and gets no empathy), but I'll put in my 2 cents worth, too.
I think the problem is the "one bad apple spoils the barrel" perception thing. Because a few homeless or poverty-stricken people do ask for food money and then spend it on alcohol or drugs or whatever pressing need they feel at the time, there can be a tendency to not want to help the others. The same thing happens when one is behind someone who is chatting on an iPhone in its cute little case and wearing $150 sneakers in line at the grocery store, and they pay with food stamps. I have witnessed that myself too many times, but irritating as it is, it's just the way it is around here. But we must be careful to not then assume that "most people" on food stamps are likewise abusing the system. Mostly likely "most people" are not.
This is frustratingly even a problem for churches, of which I was made aware just last week. The pastor was leading a discussion on the good Samaritan, and someone pointed out that the Samaritan gave the money for the care of the victim to the innkeeper, not to the victim himself. We don't know the reason for that--whether the victim was physically unable to take responsibility, or if there was a fear that otherwise he might not have used the money as intended. The pastor also said that just that day, the church had received five phone calls requesting help, which he said was about the usual daily volume. This is a small country church, with only around 400 members on the roll and perhaps 275 or so attending fairly regularly. He said that, because after paying the bills there are of course only X dollars left, each request must be considered individually. The church has "learned the hard way" that it's sometimes best to provide food instead of $$ when there is a request for food money, for example. I know this church generously helps those in the community and nearby elementary school (I taught there 20 years), and it's somewhat depressing to learn that even small churches have been burned. But, as the pastor pointed out, it is definitely our duty to help those in need, and we must guard against becoming too cynical and focusing on the bad apple. I think we need to do as our conscience directs, and if the help is misused, that is on the misuser, not on the giver.
With just a couple of decisions made differently at crucial times in our lives, many of us could have found ourselves in much different shoes now.
Bottom line, as someone said, those bad apples do make it harder on the ones who genuinely need help. As in most stories, there are two sides to this one, probably depending upon one's personal experiences in the matter. I hope that personally I can err on the side of generosity.
June and others, thankfully there are many people like you who are still willing to help others!