I used to give money to either young girls ( they have other means to make money i.e., prostitution so giving them money is equal to saving them from committing a bigger sin) and transgenders because the society has shut all doors of economic progress at them. They are few exceptions like a recent transgender doctor but maybe one in a thousand are owned by their families!
But since the past few years, I just keep a notebook in my car to record the money i would have given to the beggars. And once the total amount in the notebook crosses pre-set limit (in six figures), i give it to "one" individual with the hope that it would make a permanent change in that person's life.
10-20 rs daily wont make a difference in their lives and wont change their habits. But a substantial amount may make them start selling balloons, pens, car accessories etc and get out of the viscious circle of poverty. They might also spend all that money on drugs or something, but somethings need to be left to Allah.