In some places in the UK when a large shop has vacated the unit the landload has redeveloped the unit into a mini market with several small different independent shops within the unit and its very popular with the shoppers

Has this type of shop appeared across the Pond yet?

Like a strip mall

Those things are almost everywhere , but thankfully none are in my town. (zoning regulations )

There are also mini-malls, where a large building has been divided up into smaller shops. Bedstor, did you mean open kiosks with different vendors or did you mean a rehab/remodel job in which a big room was made into many smaller rooms?

DG Has the Thing ...Not a strip mall Koz

I think the First example I saw was in Blackpool where a Big gift store was converted into a mini market selling much the same thing ,all run as you say by stall holders all competing against each other, and unlike the 1 shop that was there before there is a lot of variety...Later on when the Factory shops became popular they'd rent space in a corner of the outlet. So if the shop sold shoes off the factory then this stall in the corner sold socks and its just snowballed .And some of these places sell you about anything to furnish,decorate a house. and in some areas these Factory shops have took over the factory with expansion
NOTE They even advertise in the posh Middle class Country Life Magazines so its classless

PS There are even Coach trips going to these places for Xmas shopping

There are several in-shop shops here. Somehow the merchandise seems to be priced higher.