Do you think we did the right thing by giving the stranger money?

Ok...so it was about 90 degrees outside.. we were at the mall.. aguy came up to me uming and/or hoping that i spoke spanish.. and explained to me that his car hd no gas and he had money at home but he had no gas to get home and his wife and daughters were in the car waiting.. He offerd to give me his drivers license in return for letting him borrow $5 for gas and he would give me $20 when he got back for letting him use the $5. I personally thought it was ridiculous and would not be able to sleep at night for taking a $15 gain on his "misfortune" so we let him have $5 and that was that... (although it took some convincing on our part to get him to agree... he didnt want something for nothing) Was it wrong of us to help him if we didnt know for sure if he was telling the truth? I dont regret our decision i saw something in his eyes that showed sincerety..but would anyone else had done this?