Yes and no. For example, I was at a gas station a couple of months ago and a guy said he was stranded and out of gas. He asked for a few bucks to help him get to his destination. I don't remember if I didn't trust him or just didn't have cash, so I volunteered to use my debit card at the pump for him. Oddly enough, he agreed. The catch, his tank was already full- all the way full. When the pump did its auto shut-off, the guy said his gas indicator must be broken. Nice try, bub. Not buying it. I dislike liars. No idea what he wanted the money for, but it wasn't gas, and yes, I was miffed. I didn't say anything- just went on my way.
A lot of the time, when I question genuine need, I'll volunteer to go get whatever the person says they want. If it's clear the person has nothing, then I hand them cash and think nothing of how they'll spend it.
About ten or twelve years ago, I had a similar experience. It was at night at a gas station, a woman approached me and said she was from out town, was a dentist (or worked for a dentist, I can't remember), and she even gave me a business card so I'd know it was true. The card showed some dentist's office in a town about 200 miles away. Her problem was that her credit card had been declined, so she needed just a few dollars to put gas in her tank. After all these years, I can't remember whether or not I gave her anything, but the next morning I called the number on the business card, it had been disconnected. I figured it was all part of a scam.
I completely stopped doing that when the same guy approached me twice in one day claiming the needed funds were for different emergencies. I told him to back up, turn around, and start walking.