Yes, considering the oil company doesn't own the gas station and still gets paid for the fuel. The person you're stealing from is the owner of the gas station who purchases the fuel and then in many areas sells fuel with very low margin in hopes of you coming into the store for snacks and drinks to make money on higher margin products. So even if they are selling a large amount of fuel, they aren't making a lot of profit to make up for the theft.
I mean, that already is used to significantly lower at-the-pump gas prices from what they actually are, and raising gas prices is an easy way to lose an election in America, so that probably won't change. Notice that in many other countries gas prices are way higher than in the US.
Depends on the cost of living and state taxes in an area. Usually it's $3.50-$5.00 a gallon/~4 liters. At the gas stations in Germany on American military bases it's about $4.50 a gallon right now.