Yep..
Supermarket competition is a strange beast, even causing problems for companies like Walmart.
Walmart wholly owns the ASDA chain here in the UK, their vision was to bring “Walmart to the British shopper” unfortunately that doesn’t seem to have happened in the sense Walmart wanted, nor have they seen quite the results they wanted (despite owning ASDA for about 20 years now).
Just this month, there has been an announcement that Sainsbury’s (the UKs oldest and at one time biggest supermarket chain) is looking to buy ASDA and then Walmart would be looking to take a portion of the 2 companies combined. Although to many this makes no sense at all, out of all the U.K. chains you couldn’t get 2 supermarkets as different to each other as Sainsbury’s and Asda.
This is currently going through completion authorities as it would create a massive chain with over a third of the UK grocery market, unlike the US, in the U.K. gone are the days when supermarkets chains were regional, they stretch the length and breadth of the country, of course certain chains have a heavier presence in certain areas to others (eg more stores in the North or visa versa), but a chain you’d find in London, you’d find it in Scotland (the one exception is Booths - high end chain store based in the North of England).
Other issue, and I don’t know if the US has this, UK chains have a “Hierachy” and get caught up with British class system (because us Brits are obsessed with class) and certain chains are seen as much better than others, and some will purely shop at one store vs another because of the message they think it conveys about them to others.
To answer your question, UK is a much smaller country than the US, with a 5th of the population, but we have Aldi and Lidl IN ABUNDANCE and have for a while, they’re still opening opening stores like madmen and in some areas (like mine) they’re almost next door to each other and they’re both doing fine, in fact causing big headaches for the original “big” chains. So as it works here with less shoppers, I can see it working over there.