My impression is that many of these beggars are earning enough to survive, albeit in poverty, so your marginal dollar is probably more effective elsewhere given most people are not making the choice to give to them or not based on EA principles and others will continue to support them. If you consider local homelessness a top priority, my guess is that other interventions than small direct giving would be more effective, though I have not looked into it.
My impression is that many of these beggars are earning enough to survive, albeit in poverty, so your marginal dollar is probably more effective elsewhere given most people are not making the choice to give to them or not based on EA principles and others will continue to support them. If you consider local homelessness a top priority, my guess is that other interventions than small direct giving would be more effective, though I have not looked into it.