The interesting thing about Lidl and Aldi is that they they have very few product lines and buy in bulk c4000 lines vs 40,000. They work off very thin margins and reinvest in their estate, they fill in gaps everywhere and saturate towns. They own mostly freeholds, so like McDonald's are a large real estate company that sells beans IMO. I've met both of their property teams and have been involved in some site finding for them both. They have maintained a large roll out of new sites while the big 4 have stagnated and it's no longer viable for them to open new stores with many sites mothballed or in sold them off for housing.

Asda and Morrison are now owned by Private Equity and struggling, Sainsburys next. Walmart saw the writing on the wall and sold out (Asda) Tesco the former powerhouse (owned by Berkshire at one point is a shadow of its former self) avoid investment IMO.