Not so. The Sainsburys I use is a superstore on the edge of the North Downs. To it's north is the large, quite affluent Warlingham middle class area. To its south is Woldingham and the North Downs Road, aka Millionaires row, so those are the clientele base.
The cut price war has moved Sainsbury's down market a bit which I don't like, so I now split some of my shop to Waitrose a little further north. But I've never seen the GB1 Roller in that Waitrose car and less of the Porsches etc that frequent that Sainsburys. Odd that it seems I think many of the wealthy are cost concious too, as the numerous recent BMWs and Range Rovers seen turning into Aldi indicate.
My position is different. I only buy the best, never look at prices and only shop at totally British supermarkets, supporting our own businesses. Hence using the best Sainburys over five miles away for my main shop, ignoring the smaller one less than two miles away. Around a quarter of my shop by value at Waitrose, and on the odd occasion of running low on something the very local small Co-op a walk away. All British through and through.
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