I've worked with the homeless and indigent as a church volunteer, and later as a pastor, for many years. It was almost always my experience that those who begged for handouts on the street would use the money to buy alcohol or drugs, not food or clothing or something worthwhile.
One of the more telling ways to find out whether someone really needs help is to offer them assistance in kind rather than in cash. When serving as a pastor, I was many times asked for help by someone needing money to "buy food for my family" or "buy gas to get back home to [wherever]" or "buy clothes so my kids can go to school". When I'd offer to buy the food/gas/clothes for them, and give them the merchandise rather than the money, in more than nine cases out of ten the offer was declined - in fact, more than a few of them actually insulted me, demanding cash instead. (Needless to say, they didn't get it.)
Now comes news that an Oklahoma City man lost his temper with an elderly lady who asked him for money. He gave it to her . . . then saw her driving off in a new car. He was understandably outraged, and confronted her. (Language alert - he's not polite.)
I note from the report:
"the elderly woman’s family ... said their grandmother has a panhandling permit and 'isn’t doing anything illegal'."
To which my reaction is, so what? Legal or illegal, she's still a fraud!
I can only repeat the advice I used to give as a pastor: give your money to a charity that you trust to use it wisely to help those in need. My #1 favorite in that regard is the Salvation Army, which has very low administrative overhead and uses most of what it receives for its work. It's very careful not to dispense cash or easily-sold items to those who'll abuse the gift.
Beware of charity scammers: there are an awful lot of them out there. Also, beware of 'umbrella' charity organizations such as the United Way, the American Red Cross or Catholic Charities. Some of the purposes and lower-level organizations they support are worthwhile, but others may be morally or ethically objectionable to you (some of them most certainly are to me!). Furthermore, they often use an unconscionable proportion of funds raised for internal expenses and administrative overhead (including exorbitant salaries for their top management).
Instead of giving to an 'umbrella' body, which then decides for itself how your money will be used, I strongly suggest giving instead to a focused, single-purpose charity that works for needs and in places that you consider important. This will ensure that your donation is used for purposes of which you approve. Yes, it takes more effort to research such charities and make sure they're what they say they are, but that's part of being a responsible citizen, IMHO.