I used to work in a Wollies/Caltex servo a few years ago. It was mind-blowing to me the amount of people who thought all of the problems we my fault. So just something to consider when you get to the counter;
1, the people who work there don't personally set fuel prices, its done by some tool in an office in Sydney. And no, the people behind the counter can't give out the phone number for this tool as much as they would love to. Remember these people that work there often have to drive to get to work and when I worked there staff discount was the 4c/l only.
2, if the people behind the counter don't follow policies and procedures, they get fired.... So when the attendant asks you to not jam the nozzle open, its because if they get caught allowing it to happen the get the sack (despite what they think of the policy).
3, The computer systems on the registers are Nazi's and will not do anything that is not allowed. So if that particular store doesn't accept a certain discount there is nothing the attendant can do weather they want to or not.
I get frustrated like anyone, but having worked in a petrol station I have realised that it takes a special type of person (thick skinned) to work in this area of customer service. So now when I go to a petrol station and fuel is $1.95 I swear at the sign on the way in and not the poor bastard working behind the counter. Not even the manager of the place has any control, in fact the only difference between the manager and the staff is the manager has to roster the staff and order stock and that's about it. So next time someone wants to have a crack at the attendant because they shut the pump off for jamming the LPG nozzle open remember if they don't they can be sacked then you'll have to complain about them being on the dole....