I didn't see that program but 40 years ago the first job I ever did (between 5th form & 6th form) was working in a pork pie factory. While the 'M&S' pork pies we made were of a marginally higher quality than the others, most of the pies were exactly the same but went out under a wide variety of labels, with vastly different prices.
During my student days, I worked at a frozen food plant. There was very little difference, if any, from the expensive stuff we produced (under the 'Ross' and 'Findus' brands) to the products which went out under 'discount' labels.
However, your question makes an assumption by your use of the word 'should'. I'd accept 'could' as a valid term but I'm a through-and-through capitalist and I believe that it's the duty of any business to screw as much as possible out of their customers. If people are foolish are enough to pay high prices, I can only cheer on those firms which are charging those prices.
Chris