I didnt' get "in" in "all of the worst in fast-food outlets & malls".

Did it mean "all of the worst fast-food outlets & malls"?

"Miracle Mile" it is sometimes called -- where a mile or more of street (usually a main thoroughfare entering or leaving a town) becomes the site for all of the worst in fast-food outlets & malls. Seems to me that it is a terrible way to enter a community and be introduced to its supposed identity. You can hardly tell one Miracle Mile from the next.
I'm with PoorRichard on this one, but I'd have used "category" instead of "set". Same thing, really.

"all of what is worst in the category of fast-food outlets and malls" is the meaning.

Also possible: "all of what is worst when we consider fast-food outlets and malls".

Emotion: smile
'In' here = 'with regard to', 'pertaining to', i.e. "all the worst kinds of fast-food outlets and malls".

Or: "the worst parts of the set {fast-food outlets+malls}".
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 CalifJim's reply was promoted to an answer.
I got it. But "be introduced to its supposed identity. You can hardly tell one Miracle Mile from the next. " got me confused, too.

I think "supposed identity" refers to "Miracle Mile". But who "be introduced to"? The writer?

"You can hardly tell one Miracle Mile from the next"? In my mind, "you can hardly tell one from the PREVIOUS" is understood, because the previous is known to you, but 'the next" is unknown, so how come you can tell one from the next"?
In many towns, as you drive into town, the first thing you must pass through is the section of fast-food restaurants, called "Miracle Mile" in this article. This is your "introduction" to the town.

So it means "introduce the visitor (by car) to the town".

"one X from the next" or "more Z than the next" are strange English idioms in which "next" often means "previous".

A funny example is that when people "ooh" and "aah" over the contestants of a beauty pageant, they say, as the contestants file in, "Each young lady is more beautiful than the next!"

Literally this means the women are getting uglier and uglier. The real meaning is that all are so beautiful that it is not possible to choose the most beautiful!

Did you like that one? Emotion: smile
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