You would pull into a service station and usually some young kid would come running out. While he was filling your tank, he'd check the tire pressure, clean your windshield and offer to check under your hood for proper fluid levels.
You could sit in the car while all this was going on or you could go into the gas station and get coffee for a quarter as well as free maps. They let you in the restroom back then too and they were clean.
Yes, gas stations would give maps out for free. Of course they would have advertisements and on the map would be other locations of the gas station you were at.
And free stuff with fill-ups, like nice coffee cups. I still have some game bird themed Fire-King coffee cups.