Even if someone asks you the directions to the gas station, you are expected not to deceive them and give them the best instructions to you your ability and they are expected to show some appreciation for helping out the society. You will face backslash if you don't help a fellow human or deceive them despite the fact that you are not receiving direct payment for your act.
Imagine you put a sign that says "The mall is in this way" and the sign is not entirely correct. It was a free sign, no one contracted you to put that sign but if it happens that your sign wastes someones time you will receive negative feedback and probably requests to correct your sign.