Really this is a nostalia-fest article, instant click-bait appeal to anyone who thinks their High Street is getting too much like every other High Street. Thank goodness the writer was in the UK, had he been in the USA I am sure he would have got himself lost in identical mini-malls.
Something missed in the analysis of Hotellings law is the difference between positive and negative competition. In a positive sense neither food cart or shop are any better than the other. However intense negative competition continues to happen and if one food cart op coughs on the food or calls in sick, the reliability of the market is boosted by having the other cart a step away. Likewise, under normal circumstances there is little reason to select one shop over the other, until one shop has a rude clerk, or a slow clerk, or a sick clerk, and suddenly reliability and alternatives is very important.
If you're in a non-Hotelling market, you win by doing something revolutionarily better than everyone else. In a Hotelling market, you win by perfect execution of a commodity.
I guess a dotcom analogy would be '07 smartphones were a non-Hotelling market when the iphone was introduced, and the android device market is clearly a Hotelling market where they're all about the same but the phone mfgr that screws up the least (hardware reliability, specs, bloatware, whatever) is the winner. The transition between those markets sometimes really trips up businesses and customers.
There is an abundance of strip malls in the US, but generally, I think more apt comparison to the British high street may be the town square commonly found in the county seat[1] of most all counties in the US (for states that have counties as such). The county seat is typically a small town in a rural area.
The central building is typically the court house, surrounded by local businesses and variety of churches, maybe a jail. There is a vast variety of architectural style among the courthouses. Some historic, some not. Some even hosted old west gun fights [2].
While being a spectacular street to walk along - the actual shops are pretty dreary. Last time I checked there were 3 O2 mobile phone shops.... which seems a bit much for one street that isn't that long.
Edinburgh council should be ashamed of Princes Street, it's truly awful. During the whole time I lived in Edinburgh and when visiting I avoided it like the plague. I think I only visited Princes Street about four times (once to buy a mobile phone :) and the others for work and an interview). The real gem is George Street, but council seem to be doing there damnedest to make a mess of that as well.
The Royal Mile is a bloody awful tartan covered tourist trap despite having some fantastic buildings.
My favourite part of Edinburgh is Leith and the shore area. I lived just off of the bottom of Leith walk and always loved dawdling across Leith Links to work in Great Michael house.
More interesting:
http://en.wikipedia.org/wiki/Hotelling%27s_law
"principle of minimum differentiation"