I agree with most of the previous answers. However..............
R1Geezer - I can understand your gripe about people not going to the empty pump in front. If there is enough space between the pumps for cars to drive thru if the pumps on both sides are occupied, then your "argument" is valid.
However, I have sometimes been filling up at (say) pump number 2 when pump number 1 then becomes free. A driver coming in behind me then goes to pump number 1 and starts filling up. I finish filling up, pay for my petrol and wish to drive away, but I can't coz there isn't enough room to drive a car thru if the pumps on either siade are all occupied, so I have to wait for the driver in front to leave.
Yes, I have often managed to reverse and go out via an alternative route, but if you have a car (or several cars) behind you, that isn't always possible.