Do you have a more reasonable explanation?
If I walk into a grocery store and buy a bag of milk, the price I am charged is the same price you and every other customer would be charged. It's based on what the store considers a fair markup after their expenses. The price may be different than what other stores are charging, but it's the same price for every customer.
In the case of the fuel depot, I was told that there is no set price; the price is different from customer to customer. Some customers are charged more, some customers are charged less. When I filled a 20 litre jerry can from their dyed diesel pump, I was charged 105.5¢ per litre after taxes. Road diesel at gas stations in the area is going for 96.6¢ per litre after taxes.
It would actually be cheaper for me to take Redtoorange's 45 gallon drum, fill it with fully taxed road diesel at the gas station, and put that in my home heating oil tank or tractor than to buy died diesel.
Am I paranoid enough to think everyone is out to take advantage of others? No, absolutely not. I see examples of generosity, compassion and fair dealing all around. I volunteer with a couple of organizations and am surrounded by many other great people. I see large corporations and small businesses alike that contribute to their communities. I work with people that have a stellar record of altruism. I spend time on forums watching people like you try to help others out.
However, I am not naive enough to believe that every person and every corporation is governed by a sense of fair play. At the extreme end I've seen companies caught deliberately and actively suppressing information about the lethal nature of their product (eg: tobacco, Ford Pinto). I've seen someone shot, cut into pieces, the pieces doused with gasoline and set on fire in a public park as a warning to other witnesses.
And somewhere in between lies the practices of price discrimination and predatory pricing. In this day and age, the most common examples are online retailers using browser history, cookies, web bugs and other profiling techniques to offer different prices to different people based on their apparent wealth (eg: Amazon, Staples, Discover Financial Services, Rosetta Stone, Home Depot, etc.).
But it's far from a modern invention. It was outlawed in the US during the Depression. Heck, there's anecdotal evidence from Jerusalem almost 2,000 years before that.
