The article kind of contradicts itself by bringing up this point, then later saying that people make a lot of impulse purchases and the average trip costs $16. I don't doubt that your anecdote is true, but it seems to not be the typical case.
Re:The economics of dollar stores
by baobabKoodaa on Sunday June 27, 2021 @05:16PM
(#27655480)
That's not a contradiction. A store can have more than one type of customer.
I've seen people (whether they be college students or just people living paycheck to paycheck) talking about how they only have e.g. $5 USD to spend on groceries for the next two weeks (because that's how much they have in their bank account, and that's when payday is).
If your choices are "something you can pay for at the dollar store at a less-than-optimal unit price" or "something you literally cannot buy because its purchase price exceeds the number in your bank account" then you really don't have a choice.
Poor people don't want dollar stores; they just want to survive.