Contrast is used to highlight price or offering differences by giving large or easily discernible comparisons. We psychologically feel better purchasing something that is less cost in contrast to a higher-priced premium good. Big differences make the lower-cost option more attractive, even if it has nothing to do with your requirements.
An example is when we are being sold on something and a luxury product is initially offered, closely followed by a comparable option at a lower cost. Negotiator 1: “How about the $3,000 Zegna suit? Negotiator 2: “That is not in my budget, my $150 polyester suit does the job.” Negotiator 1: “Perhaps the wool $1,000 Armani would be better suited?” We are more willing to pay the $1,000 as it seems like a bargain compared to the $3,000 option.
To deal with this tactic, shut down the contrast as inappropriate for the facts or irrelevant to what you want, and make your requirements clear. Consider: “I have $400 to spend on a wool suit. The Zegna and Armani are fine suits, but that level of luxury is not necessary nor desirable for my job.”