Lazy, ******** pump attendant, wastes time and doesn't want my business?

Driving down to the Kalahari from Gauteng, I refueled in Bloemfontein at the Shell Pitstop on the N1 highway. I asked the attendant to fill up my tank with diesel. At that point it had 1/4 tank in. I then paid once he was done, and I moved to the parking area, stretched my legs, etc. I started my vehicle and I got onto the highway as soon as everyone was back from the shops/facilities. Driving out on the high-way, I noticed my tank is only 3/4 full. No I ask you, why would you not add another 20L to my tank, and driving West into the Kalahari, via Kimberly, why would I not fill my tank? Towns are 130 to 150 km apart where I am heading, and you could leave me stranded.... So luckily I woke up that morning, and I filled up in Kimberly again