They may have just been shopping for a computer, maybe even a dell. Or maybe they need a computer for their kid and don't have the means to afford one and are more likely to fall for a scam advertising a good deal on a computer than for any other scam.
These all add to the probability that someone falls for a scam. Phishing is all about casting a wide enough net that the probabilities align against some of the people you hit at the time you hit them.
Victims are not just uninformed. They are also compromised, and/or incentivized to believe this particular scam, and/or unlucky enough that the scam takes place when they were recently engaged in activity that makes the scam more believable.
Seeing dell.computerdealshop.com will snap a lot of people out of it where seeing dell.shop would not have.