The first guy who pulled up on his own to get gas and paid 32 cents per gallon was being unethical. I believe that anyone who found out about this second hand, was in fact stealing.
The error to the first guy is on the station owner, everyone else is stealing.
When I have taken items to the checkout at a store and the tag has a sale price still marked on it, by law they are obligated to sell it to me at the price as marked on the item, even if the sign on the bin has a higher price. In the few instances that I have seen this, the store will immediately pull the stock until it is correctly marked.
Same applies here.