Anyone spending a considerable amount of time in LAX will hear overhead announcements that more-or-less (what? it's been awhile since i've been there, since I try to avoid LAX like the plague...) sound like:
"Attention travelers, the Los Angeles International Airport does not authorize nor support anyone who asks you for money. You are not obligated to give donations to anyone asking for money."
Meanwhile, here in New York City, I overheard in Penn Station:
"Attention MTA customers, panhandling on trains and platforms is illegal. Do not support illegal activities. If you wish to help out the less fortunate, the best way to do so is to give donations to local charities that support them. Thank you."